I saw a project that had a very clear N+1 problem in its database queries and yet nobody seemed to care, because they liked doing nested service calls, instead of writing more complicated SQL queries for fetching the data (or even using views, to abstract the complexity away from the app) and the performance was "good enough".
Then end result was that an application page that should have taken less than 1 second to load now took around 7-8 because of hundreds if not thousands of DB calls to populate a few tables. Because it was a mostly internal application, that was deemed good enough. Only when those times hit around 20-30 seconds, I was called in to help.
At that point rewriting dozens of related service calls was no longer viable (in the time frame that a fix was expected in), so I could "fix" the problem with in memory caching because about 70% of the DB calls requested the very same data, just in different nested loop iterations. Of course, this fix was subjectively bad, given the cache invalidation problems that it brought (or at least would bring in the future if the data would ever change during cache lifetime).
What's even more "fun" was the fact that the DB wasn't usable through a remote connection (say, using a VPN during COVID) because of all the calls - imagine waiting for a 1000 DB calls to complete sequentially, with the full network round trip between those. And of course, launching a local database wasn't in the plans, so me undertaking that initiative also needed days of work (versus something more convenient like MySQL/MariaDB/PostgreSQL being used, which would have made it a job for a few hours, no more; as opposed to the "enterprise" database).
In my eyes, it's all about caring about software development: either you do, or you don't. Sometimes you're paid to care, other times everyone assumes that things are "good enough" without paying attention to performance, testing, readability, documentation, discoverability etc. I'm pretty sure that as long as you're allowed to ship mediocre software, exactly that will be done.