Not quite intuitive but the system isn’t bad actually. Allow me to explain:
People don’t understand that the Crits are a “secondary source” of damage, NOT a primary damage multiplier. Same with other hit-effects. THAT is because your damage per hit DEPENDS HIGHLY on target’s defense
Let’s say your weapon ATK class is 8k there are 3 types of mobs you fight:
1 - Fallen mob, has 3k defense (DEF)
2 - Skeletal elite, has 7k defense
3 - Some “armored beast”, has 10k defense
With that particular weapon in that particular scenario: you’d deal 5k damage (basically 1-shot) the fallen, 1k damage per hit to the skeletal elite (let’s say it has something like 30k HP, meaning 30 hits), and in the 3rd case ?, exactly, your basic attack damage won’t be reliable at cases when the target’s defense is higher than your basic ATK
So, the CRIT comes as an additional hit effect. Let’s say your gear’s TOTAL Crit multiplier is 50% (meaning highly invested into Crit as a damage source to rely upon), when that Crit happens your “recalculated” ATK is 12k so you’d be able to actually “pierce through” the high armor of the armored beast
Does that make sense ?, i.e. the fight against the armored beast would look like 1 damage, 1 damage, 1 damage, 2000 damage (the crit), 1 damage… and so on…
THAT IS IF you heavily invested into Crit as your ONLY “secondary” source of damage. There were other “hit effects” and elemental damage via sockets as other sources of “reliable” damage as well
Hit effect might be a slow, or Stun, and on another item you might have a +30% more damage against slowed/stunned targets, meaning your 8k is now 10k+, so you’d actually manage to deal some damage to that “extremely high armored” class mob via those “secondary” buffs
In order for those hit effects to not be THAT unreliable, there are talents and affixes that greatly increase your hit-effect chance after X. For ex. that Pants item that was, +39% crit chance after using teleport (actually that’s the dodge roll, didn’t say Sorc only btw)
Meaning ? - after dodge roll you have a 39% increased hit effect chance to deal RELIABLE damage from your “invested” critical multiplier 
I know, it’s confusing at first, but on second thought I think it’s very nice way to make people not always rely upon basic attacks as their damage source, IN FACT, your primary source of damage are gonna be de/buffs for late game or hit effects, along with damage by skill or elemental socket/s (unless mobs have high resist % as well, then you might need to use curse-type proc effects or some type of casts to lower their def stats :P)
