Focused Attributes vs Varied Attributes

As I only got to play in the 2nd BWE and didn't play as much as I would like, I didn't get to experiment a lot of different builds with different professions.

I am wondering if it is better to focus on 1 attribute (i.e.: wear gear that boosts Precision and putting points in the trait line that upgrades Precision) or to have roughly the same number of points in each attribute.

Focusing on 1 attribute means having a lot of points in said attribute while having very few on the other ones, while varying your attributes means having a little bit of points in each one. The thing is, I don't know which would be better and/or how one could take advantage of each option.

I was hoping some players who got to play more than me could answer this question with their experience with the game so far.