Right now is one of those times when Old Navy is having an extra 50% off clearance sale. So this means that people are buying a lot of clearance items.
Here's the thing about clearance. Say there's an item that has four colors. One color could be clearanced at $3.99 and one could be $6.99 and there's nothing you can do about it. The $3.99 one was probably selling less or something. The people that decide these prices have their reasons, and they don't explain them to us because it doesn't matter.
Just be grateful that the one is so cheap, and if you don't want the more expensive one, don't get it!
Taking it a step further, sometimes people will bring two things up that are pretty similar, but not the same item at all, and wonder why they're not the same price. For instance, this woman today brought up two toddler hoodies. They were different colors and had different designs and were priced differently. She was adamant that they should be the same price. She kept saying over and over, "But they're the same thing! They're the exact same thing!"
Actually, no, they are not the same thing. This one has a sun and a rainbow and the other one just says Old Navy on it. This one is pink and this one is blue. Just because they're both hoodies doesn't mean they're the same thing! Also, they had different item numbers! They're not even the same hoodie in two different colors, they're completely different hoodies!
I'm sorry, but I'm not going to give you the cheaper price just because YOU can't tell the difference between the two. It's not my fault that you don't have a clue!
And it's a difference of a dollar anyway, so you can just calm down. If you don't want it for a dollar more than the other one, you don't really want it that much.