In the past I've mentioned "Good IPs" and "Bad IPs". So what makes an IP Bad? Well, it comes down to what are other people doing on that IP? If you're using a cheap/free/crappy VPN or Proxy chances are you're sharing that with bad actors.
Really Bad
This IP shows up on a number of blacklists. You're not able to perform a google search without getting a captcha from google. Your "United States" IP address actually returns a non-US country on a IP whois. Some sites will block this directly and prevent any pages from loading.
Bad
You're not blacklisted. But, the location services are wonky. Sometimes an IP whois will return US results, but google and various websites will target you as somewhere else. One easy way to check is to see if you get ads in a Google search? Will your Google search results be in Vietnamese or some other language than you'd expect?
Good
Your IP doesn't have bad traffic and it returns US results. Probably a good IP. Now, if it's a 'datacenter' IP you might still get extra attention. Most VPNs and cheap proxies use datacenters as they're cheap.
When Good IPs Go Bad
Now, with a VPN IPs rotate and you may not get the same one ever again. Which is kind of the point. If you use a proxy that leases an IP to multiple people you could get it leased with some bad actors. Your good IP may not be good after a few days. It could deteriorate and eventually fall on a blacklist.
A note on datacenters. Datacenters are not bad, but they're also not good. Some people will straight up ban datacenter access or flag you. Other places do not care a ton and treat IPs as good until they've done something bad. This can be used to your advantage as some datacenters don't allow bad actors. A cheap VPS that you spin up and route traffic too could provide enough cover for your tasks. Especially because you know all the traffic taken from that IP. Yes, someone could have done something 'bad' and released it to the pool. But, less likely than a free/cheap proxy. Additionally, some studies have shown that 50% of bots come from datacenter traffic and the rest come from residential or organizational IPs.
One Final Word
A 'Good IP' on one site may be a 'Bad IP' to another site. You could share an IP with a bad actor whose scrapping Amazon prices. No one else will care about that IP but Amazon. Much of this depends on the organization size. Amazon generally does most their stuff in house. So if {bad actor} has been flagged on Amazon your actions on Amazon could be flagged as well. But, smaller sites generally share tools. If ExampleA.com and ExampleB.com use Anti-Scraping.com's services and {bad actor} gets flagged trying to scrape ExampleA.com and you wander over to ExampleB you'll get blocked as well. But, that IP may be fine elsewhere.