There are certainly makes, models, and designs of handguns that are more (or less) durable than others. There are also variations within every line of products that has ever been mass produced (metallurgy, manufacturing processes, tooling, etc). Failures may occur, either suddenly or as a result of extended wear and tear.
That said, very few people will ever live long enough (or pay for enough ammunition) to wear out any quality handgun that has been properly maintained and used sensibly. Probably more firearms die due to poor or improper maintenance than by wear and tear.
I have never kept a round count on any of my personal firearms. I have a 6" Model 19 purchased in 1976 and used for several seasons of PPC competition (and some use as a duty weapon). I estimate that it has been fired at least 30,000 rounds. It is still as tight, accurate, and serviceable as it was 50 years ago.
My daily carry piece today started life about 1979 as a police department issued handgun. I purchased it as surplus about 2008 or so. Still goes BANG every time I go to the range, and probably worth triple the price I paid (S&W Model 64 RB 2").
My little collection includes several pieces from mid-19th Century, Civil War, Indian Wars, Spanish American War, World Wars I and II. All remain completely serviceable and I enjoy an occasional range visit with any of them whenever the mood strikes me.
I recall a popular song from the 1960s and 1970s with lyrics something like: "Paranoia strikes deep, into your life it will creep, it starts when you're always afraid............................................."
Personally, when I can't remember how old the lunch meat is I throw it out and buy fresh. No worries that way.