1. You are GIVING money away to the banks :( Especially because they are charging you much much more interest than they would ever let you take from them (19.99% credit card vs. 1.25% savings account)
2. It will take you THAT much longer to pay it off. By adding interest to your statement, less money goes towards your principle and so it takes more time to pay it down
3. Interest doubles or triples the original cost of the purchase. This obviously depends on how long you wait to pay off the balance but was the shirt really worth $20 (probably not) so it definitely isn't worth $45
4. Are the rewards worth it? Buy Now, Pay Later may seem like a great idea but if you don't have the money now, why would you have it later? And what about for things like clothes that are immediately charged to the card... are they worth the interest charges (see previous point)?
5. The downside of compounding. While we all know that compound interest rocks (for our savings accounts) have you ever thought of how bad it is on a credit card? I don't want to even think about how catastrophic the effects would be over time.
Long story short interest SUCKS. I hate paying it and it frustrates me to no end that I feel like I don't have a choice right now. However, I'm very excited to get started in school, find a new job, continue blogging and to really start paying off my debt!