GMail is often trumpeted as great example of a clean, well-designed web app, but I find it downright messy, complicated and unnecessarily simplistic. Everytime I need to do something simple like forwarding or adding a rule for deleting emails, I have to waste a good 10 minutes digging through that horribly designed settings menu. And even the main screen isn't that good, for example, there's no way to delete every email from a given contact, or at least not an obvious one. I try to use GMail as little as I can, because every time I do it's a real nightmare.
I've had the opposite experience. To delete all emails from a given contact....search for from:contact, select all, delete. Idk how that could be more intuitive?