In my case, when I 16 or 17 when my depression was starting to get worst as I haven't been diagnosed yet and my relationship with my mom wasn't as friendly as we are now (she used to be like my mortal enemy) back then I can write a song in just 10-15mins while normal people takes wayyyyy longer. Writing was my outlet before and it was nice when people appreciate them but somehow it was also sad as they can't really understand what was the real deal behind the words..