How's this for an analogy of why people need good bookkeeping?

Imagine it was my job to wipe your ass.

Every time you take a shit (aka spend money), you come to me, and I wipe your ass for you (take your receipts and account of the purchase). It keeps you clean and smelling fresh and I am happy to do it. But you say you don't have time to come to me and have me wipe your ass. So, you ignore me, no matter how many times I ask you if I can wipe your ass.

Now, I also advise you on how to have nice, clean bowel movements (how to spend your money properly on necessary and ordinary business expenses). Still, you sometimes eat things you aren't supposed to, and your shit gets messy diarrhea. And you still don't come to me so I can wipe your ass.

You may work with people who have no sense of smell, and they can't tell you smell like shit, so you don't care. But one day, someone comes along and notices you smell terrible. And you come to me and tell me to wipe your ass. I'm not going to want to wipe that crusty butt. You are going to have to wipe your ass, and you can't even reach that far.