How much time should pass before you skip a machine or routine if you need to wait after you are warmed up?
It’s pretty individual but I would say 3-5 min max.
It will depend on your fitness and what kind of lifting you’re doing.
For me, I stay warmed up longer on high reps/low weight.
Really, you should be seeing how little rest you can get away with and still do the next set properly.
I’m pretty sure the idea is you want to wait just long enough that you can actually just complete the next rep without fail.