A spreadsheet goes up in the budget meeting. Seventy rows, a rough number on each, a color for whether it is going ahead. The person who argues hardest keeps their project, the reliability engineer who is not in the room loses theirs, and the total is trimmed to what finance will sign, one row at a time, from the bottom.
Ask in March why a particular project is funded and nobody can reconstruct the reasoning. Ask in September why the year is overspent and the answer is the three emergent items that were added without anything being displaced. That is the real failure. Not that the wrong calls were made, but that no test was applied, so none of the calls can be defended or learned from.
The fix is not a longer budget meeting. It is giving every item the same test, at the same three points in the cycle, with the reasoning written down as you go.