The political machines that dominated urban politics beginning in the Industrial Revolution had at least two somewhat distinct impacts on people and society. One of these impacts was generally good while the other was not.
On the bad side, the urban political machines led to corruption. They were famous for requiring those doing business with the city to pay bribes. They were also famous for engaging in rather corrupt practices with respect to elections. They would do things like buying votes or having people vote more than once. It is said that in Chicago, nonexistent people or dead people “voted” when the machines needed more votes. This was clearly not a good thing.
On the good side, the urban political machines provided needed help to the urban poor. In those days, there were no governmental welfare programs. Instead, the urban political machines provided those sorts of benefits to the poor on an ad hoc basis. The poor would be given the sorts of help that they needed, but the help would be given on a personal basis by machine workers and the poor would be expected to then work for the machine (for example, by helping to get out the vote at election time).
So, the political machines provided needed welfare services, but did so at the expense of corrupting society.
Political machines were important because they brought new immigrants into mainstream American society during the Industrial Revolution. The machines sponsored firefighting clubs which was important in the days before municipal fire control. They provided social gatherings for people from all walks of life and if one pledged their loyalty to the "boss," then there could be opportunities for advancement which would not otherwise exist. The machines also provided a social safety net, giving aid to the poor and needy and providing jobs for those who needed them.
The machines were also corrupt. City bosses were necessary to getting candidates elected, and the Tammany machine controlled New York City for years. Bribery was just another way of doing business, and the ones at the top of the machine grew wealthy by providing substandard services on city contracts and receiving kickbacks. City bosses restricted inspections and were responsible for running prostitution and drug rings as well as dangerous tenements. In a way they helped the new immigrants, but in a way they also held the immigrants back in some form of poverty. If the immigrants could better themselves, there would be no more need for the machine to exist.