system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it a bad idea to pay off one loan with another loan?

I know there has to be a catch somewhere but when I looked it up I could find none. You can't just Dodge interest to a bank like that right?
gpt
You pay interest every month on a loan.

If the second loan is much shorter and/or at a lower interest rate this can be a good idea to save money overall.  That's called "refinancing" and it happens all the time.

If the new loan isn't really different than the previous one then you're just wasting the loan origination fees.  Banks don't extend new loans for free.