If we don’t understand something immediately it’s because it’s completely new info.
If we understand something immediately it’s because we already knew this info from our previous life’s, through karma.
Keeping that in mind its easy 2 understand that trying 2 tackle completely new info is hard 4 everybody & most certainly 4 them who disregard their character, mindset & already gained knowledge on the matter. It’s just karma.
Anyone can learn anything it only takes the will, desire & some perseverance, though above all compatibility with the matter or the will, desire & perseverance won’t bring anything but superficial knowledge. Compatibility depends on previous gained knowledge, indoctrinations & influences, from this & previous life’s. Incompatibility towards certain knowledge can turn into incapability 2 learn that certain knowledge 4 many life’s. It’s the Id, the me we formed that is suitable & compatible with this & not with that or with that & not with this, that depends on the karma that we fed our karma with. Trying 2 turn-around this order of evolution build by our karma through our previous actions & thoughts is impossible !
Self-knowledge is absolutely key as 2 know what 2 do & 2 learn & one must keep in mind that hardship, frailty & laziness are only the results of one’s karma or incompatibility as of yet only !