Why? They approve you for a limit let's say mine went from $600 to $1000 and then ultimately $1300. When you make purchases everything is fine. You miss one payment they decrease your limit by $300. If your balance is paid off and you owe them absolutely nothing they raise your limit and give you a deadline to make such purchase so you can lock that limit. If you don't want to make a purchase and decide not to get yourself in debt because you have other obligations what do they do? They put remove you credit line and put it all the way to $0 in retaliation. This is probably the worst I really mean it the worst credit card company I have ever dealt with. Instead of rewarding you for your payments being current and zero debt they punish you for not making more purchases despite your good paying history. Stay away from this credit line. They suck.