Don't take auto-categorization at face value
Most budgeting apps sort transactions by merchant name alone, so it's common for a charge to land in a category that doesn't reflect what it was actually for. A quick periodic review and cleanup meaningfully improves the accuracy of your spending reports.
Pairs well with a personal budgeting method
Once your categories are clean, applying a structured budgeting method on top of them -- like the envelope system or the 50/30/20 rule -- makes it much easier to see whether you're actually on track.
Frequently Asked Questions
If I fix a category, does it also change past transactions?
Usually only transactions from that point forward -- to bulk-update older entries, you typically need to select and edit them individually.
Isn't it inconvenient to create too many categories?
It can be -- overly granular categories take longer to maintain, so most people find 5 to 8 broad categories they actually check regularly works better than dozens of narrow ones.