VPNs and TOR help, but they do not give you full anonymity. Fingerprinting can track you across browsers, webpages, and even machines. Matching you up between them is much easier for a web page you've gone to with both. Such as going to Reddit from both your TorBrowser, then later your Chrome Browsers without logging in, likely has a chance that Reddit Admins could match the two visits up. If you do both at the same time, you are much more likely to be matched up. Click some links and you expose similarly opportunities to the website owner.