I think it varies a lot from product to product, and much of it is the mechanical design of the phone housing, and the durability of the jack they selected. Plus it’s really easy to accidentally put a lot of mechanical strain on it when the cable gets tugged.

MiniUSB was a busted connector design from the start, which is why the industry moved to Micro USB so quickly. Many MiniUSB receptacles in the wild were failing after thousands or even hundreds(!) of insertions.