Nothing different between working at the same company for different projects, and working at different companies. Maintenance work is easy, less time consuming

Nothing different between working at the same company for different projects, and working at different companies. Maintenance work is easy, less time consuming, and frankly mostly requires less effort. If you fall into that trap, and end up maintaining a large system that is slowly becoming obsolete, you're not building up more skills. A lot of older workers (and I am one of them) end up doing that cause that's the easy path, the one requiring no effort at all. And that leads you to becoming unemployable.