Reasons I read:
Primarily, for fun! It's one of my favourite hobbies.
I enjoy getting pulled into a world of different characters, diverse situations, humour, adventure, etc.
I also like the intellectual and creative stimulation I get from it.
And it helps me in my own writing.
Oh, yes! I forgot the one with my own writing. I am more aware now that the easiness I have in writing has as main trigger the amount of books I've read and I'm still reading.
Obviously there are many, many things someone needs to do in order to make a go at becoming a successful writer, but perhaps number one on the list is to read as much as they can. That's hailed as essential by practically every writer who is asked for advice.