I would agree that online learning is beneficial because of its flexibility. As a mother to young children, I can certainly understand not having the time to attend a physical classroom. In an online environment, I would be able to study and work when I have the time rather than having to work around a set course schedule. Many schools only offer certain courses at certain times, but an online study can offer classes to anyone at any time.
On line learning is beneficial to many because it provides people from different locations and lifestyles the ability to learn from each other. In a classroom, people obviously need to drive there to be in attendance. In a virtual classroom, people from different cities, states and even countries can be in attendance. This provides a wider variety of opinions and experiences to enrich class discussion and pespective. Furthermore, it allows people who cannot attend class to learn from the convenience of their home. This could include those with family commitments or physical limitations.
The ability to record and review which on-line learning can offer is a great plus. That said, the use of smartboard and digital technology means that lessons are easier to recall and review for students who did not catch everything in a single run-through.
The time and location freedoms seem to be a great bonus too, and flexible learning in this way offers education to a broader spectrum of people.
The convenience of online learning is definitely a plus. That is what most of the above posts have focused on. There is another less cited benefit for certain kinds of students.
Some students just don't function well in groups, especially adolescents. They have the ability to learn, but when they are in a room filled with others their age they become so distracted that educational goals take a back seat to social goals. They'd rather interact with their classmates on noneducational matters. So, when they have a chance to work on their own, without the distractions, they are more successful.
The previous posts offer some excellent answers. I would think that most online courses are taken by people who either work during the day and prefer to take classes during their free time; or for homemakers who have children to care for or other at-home responsibilities. I have only taken one online class, and I did not care for it much: I prefer interacting with the teacher and classmates to the sterile environment of the computer screen.
The main reason is that it is flexible. There are plenty of people who do not have the ability to get to a "brick and mortar" school during the time when classes are being offerred. I have many ex-students who are taking online courses now because they have children and/or because they have to work full-time jobs. These people would not be able to attend school during school hours and so online education is very useful to them.
On-line learning is beneficial for many reasons. First, those who do not have time to actually go to a campus benefit by being able to complete their coursework on-line. Another benefit to on-line leaning is that it can allow a person to move at a slower pace if needed (within the constraints of the class and instructor--if attending on-line classes).
That said, many on-line classes (especially Master's level classes) are very challenging. These classes require the student to take control of their own study skills (essentially, it can help with focus and time management).
With on-line learning, more people have access to colleges and universities (given the have on-line programs) that they would not be able to attend. Essentially, a campus grows exponentially when on-line classes are offered. By offering on-line classes, colleges and universities can expand their student body as well.
Outside of that, some students (or even people who are no longer in school) may choose to learn things on-line which they could not do in a classroom. Some people learn languages on-line, how to do things (as seen in "how-to" videos), and can even learn to play musical instruments (all in the comfort of their own home).
Although online learning is generally less effective that the traditional classroom for the majority of students in most subjects, and has been shown to decrease learning, reduce degree completion rates, and increase cheating, there are several benefits which account for its rise in popularity.
First, education is labor intensive. The single largest cost is salaries. The second largest cost is physical plant. E-courses are standardized for mass delivery, normally designed by experienced professors but taught and graded by masses of part-time faculty and graduate students who are substantially less qualified than most course directors. There is a very large student to faculty ratio and they don't require classrooms and physical infrastructure (heating, air-conditioning, janitorial services). Basically, e-courses are cheap for universities to mount, and given the dramatic reductions in university budgets (especially by Republican-controlled state legislatures and governors in the US), universities are forced to deliver courses as cheaply as possible.
There are specific populations for whom e-learning is beneficial. Single parents and people taking part time degrees while working full time find the flexibility useful. E-courses allow the disabled a variety of accommodations, the greatest of which is not needing to travel to campus. E-courses can be delivered to remote rural areas, and reduce commuting time and thus environmental impact for commuter campuses.