Preferable + Pleasant = Practical

Why? Because if it's unpleasant, then we will not be able to keep it up/maintain the practice, because we don't want to do it. 

Anything that we do not want to willingly do, is us saying "yes" when we want to say "no".... and the mind has to do lots of gymnastics to justify the unwilling "yes" and shove down the frustration at one's self for making an agreement that one did not feel 100% comfortable with...

It usually results in some sort of blow-up...like getting angry at the situation or person we made the unwilling agreement in/with...and then our perspective gets warped, ha ha ha... and the asshole lense can only see wrong/failed expectations...

SO

Preferable and Pleasant matter most; Practical is a bonus.