He finished the Chimneyspeak because the was finished
dealing with all the B.S. he had to endure. His webhost at the time actually took down the whole webcomic down months before he was done with the story, because of content issues. However, they were able to work out a compromise that allowed him to conclude Chimneyspeak, on the condition that he do it ASAP. A lot of people heaped hate of him because of the rush ending, but Jack really didn't have a choice. A pity too, because under normal circumstances he is an excellent storyteller. Truly, it was a very sad way to conclude a webcomic that was so wildly successful.
Source: I follow and communicate with Jack regularly on Twitter.
I saw that!
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