Ask HN: Whats the best and worst parts of being a web developer/designer

I'm part of a start up to make web designers/developers life easier and would love a look into the best and worst parts of the job. I'm mostly intrigued about the design and development of smaller scale websites or prototyping website but if there is anything that grinds your gears about your day to day workings I'd love to hear it.

Thanks in advance for any help at all.