Because it is produced with the management accounts, weeks after the period ended. A budget overrun in March is genuinely useful in March and merely historical in May.
By then the commitment has been made, the invoice has arrived, and the conversation is about explanation rather than decision.
Budgets sit against cost centres, and spend is coded to them at the point of entry rather than allocated afterwards.
So spend against budget is a live query. Purchase orders can count as committed spend, which is what turns a surprise into a warning.
It will not stop spending. It makes the position visible; enforcement is a policy decision and an approval workflow.
And a budget coded inconsistently will produce a confident, wrong variance. The structure has to be decided before it is useful.
A department can see its own position without asking finance, which removes a category of monthly request entirely.
And because staff cost posts from Nest to the same cost centres, the largest line in most budgets is included rather than estimated.
Yes, during the period rather than after it.
It can — purchase orders count as commitments.
Yes, posted from Nest to the same cost centres.
We will run it end to end on your own numbers in half an hour, and tell you honestly which parts Treepie does not improve.