The most common mistake I see in forum threads is someone doubling their buy stake after a string of bad features. A dead bonus does not make the next one more likely to pay, and doubling just burns through the balance twice as fast. Several long-form posts on managing losing streaks and setting stop points are collected at https://thebonusbuyslots.com, and they are worth a read for anyone new to the format. Setting a loss limit before the first buy is boring advice, but it works.