Late payments are another major pitfall of credit card use. Payment history is the single biggest factor in most credit scoring models, accounting for around 35% of your score. Missing even one payment can cause your score to drop significantly, sometimes by 50–100 points, especially if your credit history is short. On top of this, issuers charge late fees, typically $25–40, and may raise your interest rate to a penalty APR, which can exceed 29%. These costs can compound quickly. Thankfully, many issuers allow a one-time forgiveness if you call and explain the situation, especially if you have a history of on-time payments. But repeated late payments are very damaging. The lesson here: paying on time is one of the simplest and most effective ways to maintain strong credit health.