Dogs truly live in the moment so it's the moments we catch that really matter.
When training your dog it is important to keep in mind that TIMING is everything! Whatever you do or say can greatly impact what your dog learns. If you praise your dog for staying right at the moment when they are getting out of it, you can inadvertently teach them to only hold a stay for as long as THEY want. If you praise them for heeling when they are just getting ahead of your, you can train them to walk ahead instead. Try to be precise, whenever possible and if you make a mistake do it OVER with better timing. When praising/rewarding a down, be sure the dog's ENTIRE body is down or you may teach them to do a "half" down (with their elbows never touching the ground).
Is your dog getting up from a down or breaking a sit or stay too fast? Stop rewarding! Only reward when they hold it a second longer and be sure to reward quickly, while they are still doing the behavior - NOT while they are coming out of it.