The deal you were sure you would close
You had a great first call. They were keen, you were keen, you said you would send the quote. You did, eventually. Then things got busy, following up felt pushy, so you left it a week. Then two.
When you finally called, they had already signed with someone else. Not a better product. Just someone who stayed in touch while you went quiet.
Almost all of growth is this unglamorous. Catch every lead, follow up more than feels comfortable, and know which efforts actually pay. A system that holds you to those beats any clever tactic.