its not at all hard to understand
ok ill make it more clearer
higher potency the higher strength and defense power u gain in compared to a guy with same lvl but lower potency.
there r 6 ways u can increase ur potency points::
1. 1 level = 1 potency point
2. 1st rebirth = 5 potency points , 2nd rebirth = 10 potency points
3. if u have a ref item = 1 potency point
uni item = 2 potency points
eli item = 3 potency points
sup item = 4 potency points
4. 1 socket = 1 potency point
2 sockets = 2 potency points
and so on each point for each soc
5. 1 super gem = 1 potency point
that means each point for each sup gem
6. +1 item = 1 potency point
+2 item = 2 potency points
..........
.......
+9 item = 9 potency points
so
if u have
a super +4 2 soc sdg lvl 90 armor (if u r wearing it,non rb)
then
the potency points will be calculated as
super armor = 4 potency points
it is +4 so u get 4 extra potency points
2 socs = 2 potency points
2 sdgs = 2 potency points
and lastly its lvl 90 so that means u lvled from lvl 1-90 = 90 potency points (each point for each lvl)
calculating it makes it
4+4+2+2+90 = 102 potency points
thats if u r lvl 90 and wearing only the armor i mentioned
hope it helped you