Making late payments is one of the worst things you can do to your credit score.
If making your payments on time is the most important thing you can do for your credit score, then making late payments is one of the worst things you can possibly do.
Your credit score represents how reliable you are with credit. Making late payments is somewhat the definition of being unreliable with credit.
The last thing a credit provider wants to do is wait for payments and try to get money out of you.
So in order to avoid damaging your credit score, be sure to make your personal loans or other credit and account payments on time.