They all started with the Turbo craze back in the 80's. They didn't had much sense because the big capacity bikes, due to the good power-to-weight ratio, had a good acceleration even without Turbo. Add the turbo lag and all the additional circuitry and the Turbo bikes were doomed from the beginning.
I guess they had a customer base on those techno-geeks wanting the latest. For the manufacturers -at least for Honda, the first one if I'm not wrong- they had to do it just to show it can be done and they had the know-how. For the rest, specially for Kawasaki, it was a matter of not letting the competitors score a goal. A little the same that happened with 6-cyl bikes. The first one tried to score a goal, the rest had to jump on the train to avoid being regarded as second-bests, even if the bike market was testimonial.
Raul