I don't budget, but I did track my expenses in great detail.
Budgeting is not very effective at anything except cost estimation. Most people use it as a way to set hard limits on their spending but this tends to result in sub-optimal utilization of money.
The real goal is to optimize utility. For example, we spent something like 800-1500/month eating out. That's a lot of money, and the question isn't if we should budget a lower amount (because we want to save), but if we'd rather eat out less and take more vacations. Relating costs helps constrain spending better than limiting yourself.
Anyway, I had spreadsheets that tracked all expenses, then balanced it against income and savings. Same concept as any business accounting. It gave me an idea how accurate I was. I also used it to check credit card bills, etc.
It actually helped quite a bit in making decisions later, like should we move to a nicer apartment and lose that bit of money. It's much easier to visualize what you need to sacrifice when you have the data.
Kinda stopped tracking it when we spent all our money to travel around the world. It also changed my view on saving. I'm not a big fan of saving anymore. Seeing so many old people with money, but no energy left to enjoy it, was very sad. Not to mention, they seemed no happier for it. (All this within reason, of course.)
I also tend to be a model builder and more data is always helpful.
But whatever discretionary money we all end up with is normally best spent doing what we enjoy the most. Humans are normally pretty good at knowing that! It's the whole "pay down debt, save for retirement" that really has very little value to us at the time that is hard to do.