Clearing cookies does not reset everything if the site can still recognize the session another way.
If you are asking why websites know it is me after clearing cookies, incognito, or sign-out, the problem is not always one leftover cookie. Merchants can keep reading repeatable clues from your browser, session behavior, account state, referral trail, and high-intent checkout flow.
If you searched because incognito mode, cookie clearing, or device switching still left you feeling recognized, start with the demo first. It shows one controlled buying moment without pretending Cloak can erase every identity clue.