Yes, all of the aforementioned responses are insightful in my opinion. I would add that there is a growing disenchantment with institutionalised religion. Indeed, institutionalised anything. I think it is useful to negotiate this by being attentive to different modes of experience (Soren Kierkegaard a Danish philosopher made such a distinction within the context of the aesthetic, moral as well as religious). For instance, one's experience can be the result of one's socialised acceptance of basic religious doctrines where these are informed by the church (or some institutionalised accepted or formal position), or from a personalised or subjective perspective. The first is often understood as an objectivist perspective where an impersonal, detached thinking subject is concerned with determining the (so-called) truth with regards to God, whereas the latter concerns a personal, involved subject where the truth is directed towards the individual's relationship to the question of truth regarding God. The first seems to better reflect the source of people's disenchantment as it has an alienating affect on the experience of religion but also presumes this rival relation with science. The latter speaks to spirituality that seems far from diminished today.
The previous two responses provide satisfactory answers for this question, but I have a third explanation, as well. In times past, the church was the center of the community, addressing not just spiritual needs, but also social needs. This is where people got together to see their friends and neighbors, to exchange updates, and to meet new people. Particularly in rural communities, there was no other means of having a social life. Dinners and dances, quilting bees and luncheons - these were all held at a church. Women did not work outside the home, and they availed themselves of this social life even more than males. Thus, the "glue" that held the community together was usually its church.
In today's world, which is becoming increasingly urban, which is becoming increasingly connected via technology, and in which females routinely work outside the home, the church has a great deal of competition in meeting the social needs of a community. So many of us meet our social needs via Facebook, for example. Or we have social events through our workplaces. Or we find it easier to find others with a common interest because organizations have an on-line presence now. So, most people feel that the church has little to offer beyond spiritual comfort, and as the previous responders have noted, science has eroded that need, as has the greater acceptance of "alternate" modes of spirituality.
Durkheim, an important sociologist, who studied the role of institutions in society, would have found this shift to be well worthy of study. His ideas about organizations being the "glue" that held together the social fabric of a society are well worth contemplating as this question is considered.
Although no one knows for certain why church attendance has dropped over the years, I have two factors that I blame for this decline. One is the increasing wealth and material security of people in our society. The second is our growing level of scientific knowledge. When combined, these two factors have pushed people away from religion. As people have become less religious, our society has stopped expecting religiosity. This has exacerbated the decline.
The premise behind my explanation is that people need religion to help them when they feel uncertain and/or vulnerable. In these cases, they turn to the church for comfort. (Please note that I am not trying to say that people are doing this consciously. I think that most people who go to church are true believers. I am simply arguing that people are less likely to be true believers if their lives are comfortable, predictable, and secure.) Therefore, we should expect church attendance to be higher at times in history when life is not comfortable or predictable.
In the past, life was less comfortable and predictable than it is now. People were poorer and more likely to lack material necessities. Medical science was less advanced and people were more likely to have their lives turned upside down or even ended by disease or accidents. Scientific knowledge in general was less prevalent and there were many natural phenomena that people could not explain scientifically. All of these things made them more likely to turn to the church to explain their world and help them cope with it.
Today, by contrast, our lives are generally much easier than they once were. We are, on average, rather wealthy and we have high levels of material comforts. While there are diseases that we cannot prevent or cure, these are relatively rare. We can explain almost all natural phenomena through science. With all this being the case, there is less reason for people to turn to the church.
Thus, I would argue that the decline in church attendance comes from improvements in our material standard of living and our level of scientific knowledge.
There could be a lot of reasons why less people go to church today then in the past and all the reasons listed above I agree with. With the science and technology we have today, we don't need to rely on religion for answers. This is why a lot of people have turned away from religion; things aren't as much of a mystery anymore.
I think a big reason could be how people are raised. My parents didn't go to church so in turn neither did I. I know a lot of people who don't go to church because their parents didn't.
I agree that the expansion of society's reliance on the "explainable" and general scientific knowledge in general has resulted in the decline of attendance in church, however I'd also say that people have the freedom to choose an alternative belief system in today's era, and that the choice is more widely accepted.
You could also argue that many families work a variety of schedules now, and that single and multi parents families work a number of shifts that range from graveyard to weekend (including religious holidays).
Also, previously, religion was not just a way to live, but a way to comfort us in death. In today's society, there is a way of thinking among adults and children that we must "live each day like it's our last" (or, the ever popular "y.o.l.o"), and often illustrate a large part of the population that has loosened the reigns to the church's "rules" and have lived without regret (or so they claim).
Essentially, the idea of going to church for most people was always a "requirement," or at the very least, an unquestionable part of a family's weekly schedule. The idea of a "typical" American family has changed dramatically over the years, and, as the above examples illustrate, resulted in a decline in attendance in church.
This is a great question. It is one that not many have thought about, or if they did, it is not one that people have answered fully. There are theories as to why this is, but in all honesty it is difficult to determine the true reason.
I personally believe that it is because of the changing ideals and the push for individuality that has happened over recent years. In the past, atheists and people of other religions (as well as people who identify as LGBT) were viewed as bad, sinful people who were going to hell if they did not go to a Christian church and study from a Christian Bible. Obviously, people who went against the norm were scared to defy it, and therefore still went to church, regardless of what their true feelings were. Nowadays, though not to the point of acceptance as many (including myself) would like, people who do not fit those ideals are more confident in the fact that they are different (and many just don't care what others think) and therefore do not go to church because they know they do not have to.
Hope this helps!
To this question, there could be multiple reasons. As we progress in life, people are trying to become more modern and try to assess things with more modern thinking. So it could be that people feel that they don't need to go as there are other things that one wants or needs to do in life.
It could also be the busyness in one's life. People have so much hassle and things to stress about in their lives that maybe they don't have the time to even go.
Another reason could be that as discoveries are made everyday, since people are able to reason, and since more critical thinking is used everyday, people find it more logical to not believe in the concept of God. They are able to see, what they think, are the illogical senses and choose not to go at all.