The 3 D’s in dog training are duration, distance, and distraction.
Distance
How far the dog is from the handler or distractions.
Most exercises should start with the handler beside or in front of the dog (the dog should be a few feet away).
Adding distance is best done with the dog on a leash so corrections can be made if necessary and the handler maintains control of the dog.
Duration
How long the dog is expected to stay on command “stay” action
It should ramp up slowly (5 seconds, 15 seconds, 30 seconds, 1 minute, etc.).
Puppies fight more so start with a low bar (5 seconds)
Complicated by distractions and distance.
Distraction
Sounds, smells, sights, objects, events, people, other animals, and new places (higher values) need to be given lower values for the dog to focus on the handler.
Anything your dog is learning should start without distractions and be in the same room all the time until it becomes trustworthy at that point in time at that level of distraction. Only if you know the words, commands can you increase the degree of distraction and change places.