The answer is simple. You have to show proof of funds, and the examining officer has to be convinced by that proof.
Now, there are many people who have car loans, credit card loans, personal loans etc. and yet were able to show that they met the proof of funds standard. Conversely, there are people who have been denied.
There's no hard and fast rule. It comes down to this - the officers who examine your file are experienced and well trained, and can (usually) tell the difference between someone who has a standard set of debts (car loans, credit cards, perhaps a student loan) but still has enough money to meet the PoF requirements, and someone who doesn't - in their judgement- meet that requirement.
Look at your financial profile and think about it. Does it look like you have the funds?
For example, I had a car loan (around USD12,000), credit card debt (around USD8,000) and around USD28,000 in my account. In addition to that, my salary statements for the past X months showed how much money I made on a regular basis. My bank statements showed a normal level of activity - salary came in, rent was paid, credit card debt was paid, car loans were paid, etc. etc. The officer could easily see that I could have paid off my car loan much sooner if I wanted, but in the US it's very normal to take advantage of super low interest loans (mine was 0.99%) and not pay them off early.
I didn't have to clear my debt.
If you have $50,000 in loans and cc debt, and $12,500 in your account, and your account shows abnormal patterns (lots of money comes in suddenly, or there are large unexplained cash withdrawals) then the officer may not like it and either ask for an explanation or deny you outright.