Some tunes sounded very different when they were originally created!
Miranda was very transparent about the whole writing process, uploading a variety of tunes in their developmental stages. These include a completely different version of "Say No To This" (which interestingly, included a lyrical callback to another song, "Satisfied") as well as a drastically re-written "Helpless".
What's also rather amusing is that Miranda himself plays all the roles in most of the demos – so you can hear the award-winning performer trying to seduce, well, himself, in one of the videos.
Miranda reveals dozens of details in his book (dubbed the "Hamiltome") all about crafting and refining the various tunes and numbers. The demos are a fantastic way of seeing how ideas slowly formed or were trimmed back to suit the final project, often working alongside musical directors, supervisors and directors.
You can also watch how two moments from Hamilton match up perfectly here.