I don't really think that way... I think Warrior is an easy class to learn and pick up, really what most people are used to in other games. That's people say it's the best class for PvE, for leveling, etc. I have a friend that had an account and made a necro as his main, he took around 2 weeks to reach lvl 80. His account got banned and he started all over again. He made another Necro, that took him less than a week to reach lvl 80. He already knew how the class worked, making everything a lot faster and easier.
Another example: A lot of people say to me: Why don't you use focus on your off-hand to have lots of bleeds in skill 5, instead of having a warhorn that cripples enemies and do less dmg? That looks like the thing to do to have good dmg right? Well... instead I use critical chance plus bleeds on crit. Giving a lot more bleeds with warhorn than with focus.
Warrior is just easy to pick up, people normally use shouts or signets, as it is the easiest skill set to use.