There is a common assumption in parts trading and MRO sales that the order goes to the best price. Sometimes it does. More often it goes to somebody who answered while the buyer was still deciding.
A buyer with an aircraft on ground does not run a procurement exercise. They ask several suppliers, they take the first credible answer, and they move on. If your quote arrives the next morning it is not competing on price. It is not competing at all.
The overnight problem
Most aviation demand does not respect office hours. Requests land on boards and portals through the evening and overnight, from operations running in other time zones or in the middle of a disruption.
If nobody is watching, the match sits there. By the time somebody opens the portal at nine, the request is already answered by whoever was watching it.
What actually needs to change
Not the pricing, and not the people. What needs to change is that reading the request, checking the stock and drafting the reply stops being something that waits for a free hour.
The draft still gets checked. Your team still presses send. But it exists by the time they arrive, which means the conversation is still open.