some bikes don't need anywhere near the level of maintenance as others. For instance my off-road touring bike/expedition bike needs very little maintenance compared to either my mountain bike or my road bike. the difference is inital cost, design and the fact it is hub gears (a rohloff hub). Clean the chain once a week or so on a world tour (typically every 300-500 miles or so), change the chain maybe once every 8,000-9,000 miles, front & rear sprocket only got changed when I needed to change the ratios for the hub - something sutable for flat road use is not suitable for off-road steep mountain use - difference between The Netherlands/Germany/Denmark and Norway/Turkey/Tajikistan for instance. Tyres lasted 5,000 miles for my OH, 9,000miles for me. Never looked at the wheel hubs or the bottom bracket, OK I broke 1 spoke on it (my OH broke 6 spokes over 9,000 miles), 2 sets of brake pads, 2nd set are still going strong and don't expect to replace them anytime soon.
Now compare that to my road bike or mountain bike which needs the chain doing each and very time I use the bike because the lane I live on which is coated in mud most of the time, has done 1,250 miles to a chain (road bike). My touring/expedition bike is roughly 9 times the price of my road bike (in fact my expedition bike new costs more than my 2nd hand car did 5 months ago). Which has had less problems - well actually my expedition bike and I've done a much greater distance on it than the car!
You get what you pay for. Stay with derailuer gears and parts fail much more quickly, more maintenance is needed. Change technology to something costing much more initally (or run with a single speed) and have less to do in the long run.