Clear Coat over Touch Ups

[PaulyWally]

I'm not doing this. It's just a question that came up as I am learning about proper auto painting. I have often heard you cannot clear over a small repair/touch up. Although, some sources I read stated it can be done if the area is small enough.

My question is, why is this a no-no? Is it just cosmetic? Is there a loss of integrity in the clear coat?

 

[Barry]

It's done every day, and I personally have done it who knows how many times.
I have a car I did around 24 years ago, and the upholstery shop put a 1/4-inch chip.
I never buffed the spot, and over 35,000 miles since, I can't find it but know where I did it.