It’s a good question; and it depends on you and the effort and commitment you bring. Your coach assists you to accomplish results faster, however results always come from you and your efforts. Your coach encourages you to work smarter and to be more accountable to your word but make no mistake about where the change comes from, it’s all you and your team.
Having said that, most people experience results very quickly at first. The perspective, direction and tools generate a spike in performance. After that, the focus is on sticking with it and expanding your impact through others.