Yeah, depending on the connector you can easily start getting loose connections after a few hundred cycles - I did. You can get there very quickly if you switch antennas around a few times a day to check things out.
The number of “mate cycles” a connector is rated can vary wildly. Some precision connectors are rated for thousands:
https://www.keysight.com/main/editorial.jspx?ckey=632781&id=632781&nid=-11143.0.00&lc=eng&cc=USSome cheap overseas connectors are seemingly rated for a number less than one.
Most connectors seem to have manufacturer ratings for mate cycles in terms of hundreds of cycles. This doesn’t necessarily mean that the connector outright fails completely, it means that it doesn’t meet some specification any more (for example, the thickness of the gold plating). The connector may still be perfectly useful for most applications.
If the connector is abused, all bets are off. Most RF threaded connectors have torque specs, but you rarely see a torque wrench used. Some connectors come in 50 ohm and 75 ohm variants. They look similar, but internal pin diameters are different. If you mix the two, you may damage one of them.
This article had some good points about connector mate cycles:
https://www.cirris.com/learning-center/product-articles/other-products/227-connector-life-cyclesWhen you buy hamfest connectors and adapters, who knows what you are getting. “You pays your money and you takes your chance.” I try to stay with well known brands like Amphenol, and avoid the ones that look like they have had a rough life.