I absolutely agree with you. Starting entrepreneurs often have to say yes to anything just to get their feet wet, but as they progress, they MUST be willing to say no to engagements that might not be time consuming, but will take away from their “mental energy” or “capacity” as you mentioned. The only caveat is, how do you know if something you say no to won’t be an engagement that will change your life, or bring you a great opportunity? That is something I always struggle with! Anyway, I really enjoyed this article and I will be following you!