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Frankly even back in the golden age there was always the ideas that ANY of these heroes don't quit and don't back down. They stand up for what they believe in and fight to the death. The idea that Bruce Wayne can just chill somewhere watching TV while some other kid is being orphaned somewhere always HAS gone against the grain of ANY of the heroes.
When Robin showed up, he took on a more fatherly role and the comics became more kid-central and there was the occasional fishing/camping trip or watching a movie or doing generally relaxing stuff did happen more. When the cops need him and that spotlight goes on... he would never turn his back on it.
Then as time goes on Batman above all others became MORE obsessed and MORE determined. To push his body and willpower farther than human limits. The thing is... even if he thought or hoped that Jean-paul COULD take over for him... he was wrong. Bruce is the ULTIMATE human. Ultimate fighter/athlete/scientist/Detective... and no matter who he picks to wear the cowl, they won't do as good as he could. He's still needed. Other heroes MAY get hurt and retire... but it's become totally against everything that Batman stands for.
The only time I DID like it... was in Batman Beyond. It wasn't his body that gave out. Having a heart attack is an inconvience… it was desperately grabbing that gun and threatening to kill the punk that pushed him away. He had to break his own code and didn't deserve to be Batman anymore.... I could live with that. Losing Jason in DKR... That kind of worked too. You have to break his willpower somehow, not just his body. He isn't looking for an escape hatch to live a 'real' life.
I really thought Kingdom Come nailed Batman well. When his body couldn't handle crimefighting... he built drones and controlled them remotely. Either way, nobody else was getting mugged in his town