It is unfair to compare Alesi with likes of Vettel, Schuey or Alonso. Even Button.wesley123 wrote:He came in F1 with the Tyrrell, and impressed back then. But from that on he never truly evolved, you see lots of drivers impressing at their debut, they then grow out to be something big. Take an exampe to Vettel, Schumacher, Alonso or Raikkonen. They all came into F1 and impressed, and so did Alesi. However the improvement those guys I named made, Alesi never did so. Some drivers 'evolve' rather quickly, like Schumacher or Vettel, some take a lot more time, like Frentzen or Button, and Alesi was just one of those that never grew.
When his big break supposed to come he was alongside Prost and had 21 point compared to Prost's 34. Pretty respectful. Next came '92 and '93 -- nuff said. Then '94, where he had a big crash, but also some solid performances marred by car's unreliability. Then '95 -- probably his best year, and he had some good drives. Next he went to Benetton -- and the team was declining. Next Sauber, Prost and Jordan -- how could he "grow" in a teams like that?
You mention Button -- when exactly did you see his growth, when he got a best car on the grid?
All the drivers you mention had their time in best cars on the grid.
Alesi surely had his problems -- most of all he couldn't control his temper at times, outdriving himself. But there's a good chance he could be calmer in a car that is both fast and reliable.
My point, with the cars he had we just don't know.