The problem
Most budgeting apps revolve around reconciliation after you spend. They ask you to go back, organize the past, and classify decisions that have already been made. Understanding the past can help. But it does not replace deciding clearly in advance.
Worse: it often creates guilt. It turns budgeting into a chore and requires people to build a habit of reviewing, categorizing, and explaining every purchase. Not everyone wants to do that. Not everyone can sustain that habit. And for many people, that work ends up becoming a second job.