I started on hub gearboxes because of a derailleur event that was the final straw for me. It must have been one of the last Sachs-Huret oval chainrings that simply folded up under me and took out both ends of the derailleurs with it as I stood up on the pedals to attack a seven-inch high curb because if I didn't I might as well go straight to the physio, that bike had so little compliance. The entire drive chain locked up solidly. I was lucky not to take a faceplant. Fortunately all this happened about thirty yards from my LBS, not out in the bush, or the bike would have been thrown into the ditch. It was the end for me with derailleurs. I carried the bike into the LBS and gave it to him; he fixed it and sold it on, and the new owner waved deliriously at me for years when we passed on the road: he thought he bought a bargain, but I hated the shoddy, careless, incompetent design of that expensive POS. After a couple of Shimano Nexus hub gearboxes, which under me proved superior to derailleurs in operation but not sturdy enough, I got a Rohloff when we moved up a steep hill, and haven't looked back a minute since then.
Thank God for derailleurs: they led me to the Rohloff Speed 14.