Does it ever happen to you? You pay your purchases and bills cash or online, but you also mark those sales on an accounting sheet.
I check my home accounting weekly against what my bank excerpt shows. Most of the time both are equal. However, today I noticed that my post for electricity/gas was way too high. And that the post for housekeeping purchases was too low. Then you need to check back all your bank details to find where you have gone wrong. I found the mistake - I had put amounts in the wrong column!
Yes, it's not always easy to keep the balance in check! Sometimes you have to be quite creative as well - especially when faced with unforeseen expenses!
Still, I've never went into the red on my bank account. I have always lived to the rule: don't spend what you don't have.
What about you?