Everyone wants to make a great movie, because especially in franchise-potential IPs, if you make a great movie, you'll not only make money on that one, but on future sequels, prequels and spin offs as well. I think the problem/difference between something like the Star Wars universe and the Transformers universe is the people in charge. Michael Bay put out the first one and it made a lot of money, so ever since then, he has been offered to come back because they know his movies make the money. Disney have mapped out the next 50 years of Star Wars movies and they know that they have to make their movies great, or otherwise a lot of potential moneymakers in the future won't be made because they screwed up their own cinematic universe. With something like Transformers, the stakes are not as high. If Transformers 5 flops, or whenever Michael Bay is done with it, they can just go back to the drawing board and maybe have a different take on it.