I understand that some websites are poorly implemented and can't handle hundreds of requests. IANAL, but AFAIK whether it's a DOS attack or not partially depend

I understand that some websites are poorly implemented and can't handle hundreds of requests. IANAL, but AFAIK whether it's a DOS attack or not partially depends on the scraper's intent. In this case, after volunteer engineers invested in their system, it turned out that they created a DB connection after each request, maintained it for 10 mins, and didn't reuse it or close it. So the number of DB connections quickly reached its limitation and couldn't handle the following requests. Similar problems happened with other library systems developed by the same company. The prosecutors dropped the charge citing his scraping was reasonable, and he didn't have any malicious intent.