Would turning and A/c unit on and off every day shorten its life? How will this affect the condenser?

I think it won't shorten its life at all. The condenser, itself, turns on and off every time the thermostat turns it on or off.

Can`t see that turning it off and back on would hurt the life of unit,this is what the thermostat does. Although some are led to believe (me included) that turning a condenser off and waiting till it get hot in the home will cause it to work much harder to get to the tempature back to the comfy zone. And this uses up the power that was saved by turning it completely off,would be better off to raise the thermostat about 10 degrees so the condenser won`t run as much and then when house starts getting hot,and you lower it back down the unit doesn`t have to work as hard getting the temp down 10 degrees rather than maybe 20 degrees

I tell people not to change their settings any more than 4 degress. Depending where you live it can run for 15 minutes for each degree you want it to cool. Better to let it run a few times an hour than run for three or more hours.