With a reward of 0.1% with each attempt, it means he needs to make a total of 1,000 attempts for him to master it. If he makes three attempts per day, he will be done in 333 days.
So he can shorten something that takes the geniuses years to achieve on their own to less than a year simply by torturing himself three times per day. There is no way he isn't going to take that deal.
In the past, he would need to beat an anvil with a hammer or carry heavy weights in order to train. But he doesn't need to do that anymore.
All he needs to become stronger is to look at something. It reminded him of all those times his mother was always looking at a book and calling the process of reading it cultivation.
Even though his mother had told him that once he reached the second mortal coil, he wouldn't need physical exercise to train himself, he still couldn't believe that there was something so good.