Talent, it is something latent to a person. Something unique and different for each person. How well they can understand things, how well they can control and interact with mana. These are things that make or break an adventurer. Even those that aren't mages must be able to reinforce their body to even qualify for the B-class. Mana drives the world.
It is common knowledge that apart from those with the right affinities if someone were to house elements in their body they would die from the battle going on inside of one's body. Thus breaking through one's limit is impossible.
But there is also something else that can make or break an adventurer. Mana. their amount, how much they possess.
The wizard Avius who specialized in the study of magic formed a theory. What if magic wasn't a simple matter of affinity? Having a large capacity to contain water elements in your body was considered talented and in tune with the ways of water magic. Any other element that you were less proficient in you were considered untalented.
Having a capacity to hold each of the different elements is what creates affinity. To increase the amount of mana a person can hold is a matter of uncovering their capacity.
This increase in mana can be attributed to gaining access to more of their true capacity. It is akin to cleaning a container by emptying it and then blasting water inside. Getting rid of the water and then starting from zero. This also explains why battles that often force one to hurriedly empty their reserves and try to recover mana at the same time can lead to so-called breakthroughs.
That was why some reach the peak while some die while overexerting themselves, they had reached their maximum capacity. Avius hoped that with the help of alchemy one's capacity could be increased. Maybe one would even be able to house elements they previously weren't able to.
These ideas seemed far too good to be true. Not only that but they seemed too out of the norm. Many other scholars had research pertaining to affinity and admitting that they were wrong was obviously not something they were willing to do.
Thus, nobody agreed with Avius' words, especially not with his analogy. His theory was declared to be illogical and a waste of time to research, Avius was verbally blasted and his reputation as a great scholar was tarnished.
Avius disappeared soon after and was not heard of again. Some say he went into seclusion to prove his theory correct and others say he got himself out of the way.