When people pay for a ticket, if the aeroplane hasn't got the legs to do a trip in one go without going below final reserve, we plan for a refuel stop enroute .
if during the planning stage you have doubts of making it, either pick another aeroplane that is up to the task, or stop enroute.
How much into your reserves are you willing to go?
Another question for you sunfish, if you were doing that trip as a NAV test during training, and you pushed on through and landed below your final reserve, what would the outcome have been?