The more simple you can keep your golf swing, the easier it will be to repeat and be consistent. One big part of this is to eliminate extra or unnecessary movements in your swing. Just focus on the fundamentals and keep it simple.
Extra movements in the swing can be anything from a lift or a sway, standing up or coming out of your posture, or something similar.
If you are making extra movements in your swing, you will have to compensate to hit good golf shots and it's just more work to do. It's a lot easier to be consistent when you're not compensating and not making extra movements in your golf swing.
Any kind of manipulation of the golf club during the swing can also be an extra movement that you don't want. Some examples of this could be rolling the arms which changes the club face angle. Or, changing your posture or your height by coming out of your angles during your swing.
If you stand up during the backswing, you'll have to dip down on your downswing to counterbalance this and it becomes something you have to rely on timing too much for in order to still hit good golf shots.
Golfers who have complicated golf swings with lots of extra movements will have to practice more to get their timing working correctly. If your golf swing is simple and doesn't require a lot of compensating, you won't need to rely on timing as much and it will be easier to be a lot more consistent.