Why are iPhone chargers so horrible?

I do my best not to, but somehow my iPhone 5 charger ends up breaking after about a month and I buy a new one and the cycle repeats.

Are you pulling out the plug by grabbing onto the wire? If so you should grab onto the end part of the plug. I have just found that to be a common mistake people do.

I get through at least 2 chargers a month, it's a nightmare! But I've found some ways to stop the cord breaking…
Get the spring out of a pen and wind it onto the cord and put it at whichever end breaks.
Don't bend the cable, sit upright when you're charging, don't lean the wire on your leg ect, when you're using it during charging.
Try not to use your phone when charging, if you turn down the screen brightness you'll save a lot of battery life, and as long as you aren't glued to your phone 24/7 you should only need to charge It when you're sleeping.
A link to a video showing how to do the spring trick, there's plenty of videos out there doing the same thing if you need a closer look at what to do, this was just the first that showed up

Never had an issue with mine.