"[...] Linus moved to it and most of the developers followed. They stayed in it for three more years before moving to Git because BitKeeper wasn't open source."
Um, the "because" part is not quite right.
Um, the "because" part is not quite right.
If all free software activists had accepted the compromise of using the free-as-in-beer BK, git would never have been created.
They stayed in it for three more years [...] because BitKeeper wasn't open source.
but
They stayed in it for three more years before [moving to Git because BitKeeper wasn't open source].