There is too much pressure on airlines today. Too many airlines are chasing after a limited number of passengers and thus offer "low" fares.
With low fares that means that revenue might be impacted. How much money will be there be for regular maintenance? Pilot Training?
There is too much pressure to return a plane to service. It is very easy to rush and thus to overlook things.
I don't that any airline will deliberately cut back. I think that we are seeing is trying to stretch a low budget to cover more.
There is often pressures on getting planes back into service. This leads to rush jobs. It is easy to overlook things.