I stumbled upon the phrase focusing on the warts in a blog post. The post is about a programming tool
Following is the context of the phrase:
Rather than focusing on the warts, I hope this post will explain to newcomers the Places Model that will help motivate Git is complicated (and yet amazing).
I've searched ODO and UrbanDictionary with no luck.
Also, I found it's a widely used phrase with a Google search. I can guess its meaning was focus on the difficult, ugly part of sth. But I'm not sure my understanding is accurate.
Hope someone could give me a definite explanation.