Online casino bonuses may help. They extend your time at the tables or slots, give you additional money, and sometimes let you try games you wouldn't otherwise risk. However, mishaps can be frustrating. Ironically, neither bad luck nor unfair casinos cause most player problems. Small, preventable errors before a bet cause them. Once you know them, these mistakes are easy to avoid. Let's examine the most common. Grabbing a bonus before reading a single word of the terms This is probably the most common mistake of all, and it happens all the time.