I've studied about dear ol' Ludwig a bit -- not to any sort of thesis or dissertation level at all, just on my own.
In a word, Ludwig was an asshole -- especially when he lived in Vienna. He was filthy dirty, unorganized, irascible, nasty, and a PITA for those who knew him. Many have written that that quality came about because of his increasing deafness. As I am hearing impaired as well (I can't listen to a Netflix program without CC augmentation) and you can completely forget about me going to a movie -- I don't understand 75% of the dialogue), I can fully understand Ludwig's general level of pisstivity since he had none of those technological tools at his beck and call.
His composing was as unorganized as his non-hearing was. He carried his notebooks to various Vienna coffee shops where he'd hang out for hours, writing, scribbling, canceling, re-writing, always searching for what he heard in his head but could not readily hear live. Frustrated, angry, he lashed out at those who respected him, then he'd collect his notebooks and lope off to his apartment.
And to know that he composed music such as this that would reach out and touch a toddler to that extent almost 200 years after his death. That, my friends, is a legacy.