Practice doesn't make perfect, practice makes permanent
One of the biggest pitfalls with the non-beginner and intermediate lifter is doing "junk" reps.
A tell tale sign of your volume not being quality volume is getting through your sets x reps at the prescribed weight every week, then when it comes to max out day, you get the same or worse than your previous max and your technical flaws are still the same.
Intent is the name of the game when performing volume, 50-80% has a lot of room for error in terms of effort and movement quality, the point of performing volume, speed work, reps etc. at sub-maximal loads is to practice voluntarily producing maximum force with good technique. If you're usual pitfall in the snatch is the bar loops out and you don't shrug on the pull, your intent needs to be bar close, shrug to finish.
Otherwise you fall into the same trap you were before, looping the bar out and not shrugging. If you spend 100's of reps reinforcing the same technical flaw, you best believe it's going to rear its ugly head when you go to your max.
The key to making your reps count, whether it's on the competition movements or the variations, set yourself a target/focus point for the lift and make sure you're drilling it on the warm ups and working sets.