So I take it you only did stuff during the daylight hours then? I don't always have that luxury, there are many times I'm out at night after sunset or before sunrise working in my coop no matter how many windows or features I have there wouldn't be enough light to see properly in those instances... My artificial lights are on from 5AM to 10PM normally (I sometimes adjust if they are not returning tot he coop with sunset), and during the winter when the sun is setting at 4:30PM, it's quite dark in the coop by 6PM and since I do a vast majority of my coop maintenance between 6 and 10 PM that makes things much harder without light...
Of course there is no 'need' for light, but I find it to be a very worthwhile creature feature for me personally as do others, same with heat, I find it much nicer working in a 35-40° heated coop then the -10° it could be during the winter... Again neither 'needed' no but for me they are well worth the investment and trouble...