One thing the limit switches are for is repeatability. If you need to stop for some reason mid cut, or skip a step (or more), or want to go back to the same place after turning off the machine (it will move when turned off, and often jumps when turned on) you need a reference. That reference is the switches.
The stock switches, though pretty good in use, are a bit sensitive to overtravel - clunking something into them seems to be pretty hard on them. The plunger will still plunge, they seem mechanically ok from the outside, but the internal contacts are messed up. Use a multimeter to test the switch with the power off.