One reason is that you'll take a net 'loss', creditwise. You take a hit or more for the INQ, you take a hit for seeking and obtaining new credit, you take a hit to AAoA, and then you have nothing to show for it (no positive payment history, to increased CL for utilization.... nothing). You'll have lost FICO points that it will take a year to fully recover, for absolutely nothing.
After one year, you'll have seen your return on both the INQ, and the "new credit". After two years, your AAoA will have recovered nicely, and you'll have two years of stellar payment history upon consideration for other credit-- which is what a lot of lenders look for. Remember, other lenders don't rely solely on your FICO score itself in determining if you're a good lending risk. They actually review your history with other lenders. Opening and closing accounts, without any tangible history, just won't give you that.
