Why use the Three Piece Plan?
Because you don’t have to keep up with it daily!
I think this is the number one reason that people can’t do a category or software based budget.
Constantly having to divide up receipts, enter categories, shuffle money between envelopes (the only thing the envelope method gets most people is paper cuts!), and what do you do when you can’t figure out those last few pennies? You just quit.
I think it’s the same thing for diet plans that have you count calories! The only people who make money on that plan is Weight Watchers. No one has time to count calories every day… and no one has time to count every penny they spend!
So, why use the Three Piece Plan? Because it does not take any daily work.
Set it up once, let it work for you, and make minor adjustments when your income or your outflow changes.