Why does my battery keep dying even though I drive every single day?

This is something that genuinely confused me for a long time because I always assumed that driving your car regularly was enough to keep the battery in good shape. I drive every day without fail, mostly to drop the kids at school in the morning, stop by a supermarket, maybe run one or two other quick errands, and then come back home. It never occurred to me that this kind of routine could actually be part of the problem rather than the solution. My battery died for the second time in about fourteen months last month and I was really frustrated because I felt like I was doing everything right. A colleague at work who used to be a mechanic told me something I had never heard before which was that very short trips can sometimes be worse for your battery than not driving at all because the engine does not run long enough for the alternator to put back the charge that was used to start the car. Each short trip takes a little bit out and never quite puts it all back and over weeks and months that adds up into a slow decline that you do not notice until one morning the car just will not start. After he explained that I went and read more about it and actually came across a page at khaleejweekly.com/short-trips-drain-car-battery that broke down the whole process in a way that finally made it click for me properly. The science behind it is not complicated once someone explains it clearly but it is the kind of thing nobody really teaches you when you first start driving. I have now started taking a longer route home once or twice a week just to give the alternator enough time to do its job properly and I also got a basic battery health check done at a petrol station which only took about five minutes. Small changes but I am hoping they make a real difference this time around because buying a new battery every year is not something I want to keep doing.