[rendaw]

That manual skips over the reasoning too:

> This is called the single-entry method of accounting. But we’re not going to do it this way;

Why? So you have a graph now, what does that allow you to solve? What issues will you hit with single-entry (maybe with tags)?

I _think_ the simple answer is that if you have multiple accounts, any transaction moving money between them needs to decrease one if you increase another or else you'll magically gain/lose money in your records. Then if you use it to answer something like "do I have enough money to buy X" you'll get an incorrect answer. It doesn't seem to be a suggestion/improvement/technique and more of a mathematical reality for this model.

The double entry requirement for money entering/exiting the system (salary, sales, payments) doesn't seem to matter for that though.