Taurus and Sagittarius have very different energies as a couple. Taurus likes stability. It's an earth sign. In astrology it means that that sign needs security and wants to lead a life of familiarity in a sense, something that is, when I say familiar, something that works well, and if it works well once then Taurus wants to continue doing that. Sagittarius on the other hand is a fire sign and it is the sign in astrology that represents freedom. Sagittarius is looking for adventure and getting out and experiencing the world. The first thing that Taurus tries to do with a Sagittarian to whom he or she is very drawn because, like a moth to a flame, the Taurus is very interested in the Sagittarian's free spirit. But, the first thing the Taurus will try to do is to curb that free spirit. So, Sagittarius immediately tries to get out of the net.
As a business partnership, they might be a little better because Sagittarius is willing to try new ideas and Taurus is a very good business person. As a love affair, once the sexual sparks die down, and they do very quickly because what Sagittarius is looking for in sex is fun and what a Taurus is looking for is a deeply passionate experience that will last and last and last. Once that dies down, then they have so little in common that it is difficult to sustain a long lasting affair, much less a marriage. In general, Taurus and Sagittarius have very different energies.