I'm confident or arrogant enough to say that I think I'm a pretty good coach. I can also start another journal with more content if I reflected on all the mistakes I've made. Those mistakes have shaped me more than any successes.
(I made a conscious decision to spare you of all the clichés that pertain to making mistakes. You're welcome.)
The more you plan, the more you coach and the more "what-ifs" you rehearse in advance, your chance of erring decreases. But it still happens.