While I have greatly enjoyed the visual effects of Jurassic Park, seeing it for the first time has also greatly disappointed me, because in my opinion the movie script has been much, much worse than the book that I had read some years before that.
In the book, the catastrophe that happened at Jurassic Park had been convincingly presented as an unavoidable consequence of the complexity of the project, arguing thus that there are limits for what humans can create and control.
On the other hand, in the movie the main idea of the book has vanished. There was some mumbo jumbo about "chaos theory", but that was just ridiculous. Instead of that, the catastrophe of Jurassic Park was presented as a consequence of stupidity, incompetence and bad luck.
Perhaps those are more realistic reasons for causing the failure of something like Jurassic Park, but this change has separated completely the movie from the book that inspired it, because it has made the catastrophe look like an accident that should have been easy to avoid, dismissing silently the intended warning message of the book.