[dagw]

If everybody else is offering a 70% discount and you're offering a 15% discount, chances are people aren't going to bother looking at your offer. Also since there is a certain amount of hassle and risk (if its a business you've never used and heard nothing about) in using Groupon from the customer side of things, I'm guessing most people won't bother if the discount is to small. Saving 15% just isn't worth it, especially if you're saving 15% at place you're not even sure you really want to go to.