That, and it's a good diagnostic tool to determine if e.g. you have shady utility companies who like to try to double-post your payments, or screw up and don't cash your check/take your payment and don't inform you about the problem, but then later try to get up your nose about being "late." Both of these things have happened to me at some point in history through no fault of my own.

Or to just catch suspicious/fraudulent charges in general, which I think these days especially everyone will agree is a potential happenstance.

What "ought" to be is one thing, but being able to readily check what actually is, is also vital. I always check my transaction records regularly to make sure nothing is going on behind my back that I ought to know about.