Helping a competitor may cost them in the future, but I am guessing they got paid enough money in the present for the consultation to be worrh the risk.
I cant speak for Toyota, but they probably also would feel their own future would look bleak if their competitors died off - a good healthy level of competition is good for all players in the market, and it drives up innovation and drives costs down for consumers. In a very direct way, having able competitors ensures Toyota stays strong and doesnt stagnate.
See my comment above, but it is important to remember that Toyota did not have any production facilities in the USA at this time; they were not sure (purportedly lazy) American workers could or would conform to the Toyota Production System.
Also, at that time GM had more cash than Toyota's Market Cap. [citation needed] [1]
1. I wish I had better source for this, but Roger B Smith spent 80 billion on automation in the 80's, and Toyota's Market cap was 31-45 billion in 1992.
I cant speak for Toyota, but they probably also would feel their own future would look bleak if their competitors died off - a good healthy level of competition is good for all players in the market, and it drives up innovation and drives costs down for consumers. In a very direct way, having able competitors ensures Toyota stays strong and doesnt stagnate.