Stability. So many people think it is about locking everything down as hard as you can. Unfortunately, that is NOT efficient or powerful. In fact, it is often a weak way to do things.
I am firmly of the belief that your brain often knows how to do something well and if you get in the way of that by "turning on" muscles, you often choose a less efficient strategy.
Stability cues (tighten your core, ribs down, turn your glutes on, shoulders down and back, etc) are meant to be helpful, not make you worse.
So how do you know if you are "overcooking" the cues? Test/Retest of course! This LONG held method of testing has been around for decades. How else do you know if something is helping or not?
If you stability cue/s are about thinking about a muscle or contracting this or that, I suspect it is going to be inefficient. Your brain doesn't consciously think about what muscles to contract and so that shouldn't really enter your consciousness.
Rather, your brain works really well with tasks - touch your nose, catch the ball, get dressed, punch, kick, block etc. You think of the goal and the brain puts the pieces together to make it work.
So next time you hear your coach talk about engaging your core, just think "keep my back still"...have you noticed that the best cues tend to be actions rather than contractions? Butt out, look here, armpits up, press up, stand up straight etc etc.
Here is a little posture video I did a little while ago to illustrate some common posture cues that are overcooked...