Why do so many small businesses miss so many leads?

Curious to understand this from real operators, not from theory.

I’ve been talking to a bunch of small business owners lately (restaurants, gyms, clinics, contractors), and almost all of them say the same thing:

“We miss a lot of calls because we’re busy, understaffed, or closed.”

What I’m trying to figure out is:

• How big of a problem is this actually (how many calls missed/day)?
• Is this something you actively track?
• Do you ever check how many people don’t leave voicemails?
• And honestly — how often does a missed call = a missed customer?

I’m building something related to this problem, but before I go deeper I want to hear from people who live this reality every day.