Even though this game is pretty old, but personally I don't think this is an excuse for not elaborating some of the skill descriptions. There's no visibility to how long does a buff lasts or whatsoever. For example, mana shield's duration, how does the mastery skill affect the element spells cast dmg/rate, how often does freeze effect procs from level1-5, bla bla bla a lot more to go.
Not sure if anybody agree with me though, I am coming from the view of a new player(never played this game before), the description just doesn't really help in deciding or judging whether it's worth taking. Hopefully one fine day, they can actually add in more useful descriptions like the buff duration, % that a certain effect will proc and so on...