Does pollination end the life of the bloom?

[Stray59]

Hello everyone - hope you are having a great day!
I was wondering - When you pollinate a flower, or remove the pollina, does the flower start to die off? Doesn't the pollination end the need for the petals and scent? I want to cross some plants, but hate to lose the blooms; I will if I have to, but it will be with moist eyes when I do! I have been wondering this for a while, but keep forgetting to ask.
We are snowed in in Indianapolis, Indiana, USA, so I have a day to watch the hometown football team, the Colts, play rivals Houston, Texas, drink coffee and post on the board!!
Have great New Year!
Steve
Thanks for any input you have on this -