(Reservoir Dogs) Mr. Blonde's true motive.
In the film, as we all know, Mr. Blonde is killed by Orange as he's about to burn Marvin the cop alive. When Eddie returns, a dying and desperate Orange tells him that he was gonna kill both him and the cop, blow the hideout up when everyone else returned, and run off with the diamonds.
Eddie calls bullshit on his story, as unbeknownst to Orange, Blonde was on close terms with him and his dad, after having done four years in prison after being caught at a company warehouse full of hot items without ratting the two out. To Eddie, it wasn't believeable that a guy who did several years in prison for them to rip them off the second he got out.
But I think that had the job gone as planned, Blonde's plan WAS to burn the place down (killing everyone) and run off with the diamonds.
First off, just because he did his time "like a man" and didn't rat out Joe or Eddie, that doesn't mean he wasn't mad about being in jail because of them. He probably stayed quiet either out of pure principal of not being a rat, or as a long term strategy so that they felt indebted to him for keeping his mouth shut (or both). He has all the motive in the world to rip them off if the opportunity arose.
Secondly, Blonde has been shown practically from the beginning to be a cold blooded psychopath. If he has no problem with killing innocent bystanders during a robbery, or cutting a cops ear off just for fun, I'm sure he has no issue killing Eddie and Joe after he was forced to spend year in prison because of them.
Another piece of evidence that I think furthers my theory is already having lighter fluid handy when he went to burn the cop alive (before Orange killed him). Why would he just randomly have that in his car the day of the heist? Maybe because he planned to burn something to the ground.
So TLDR: While Orange had no way of actually knowing it, Blonde did actually plan on burning the hideout to ground, kill everyone involved, and run off with the diamonds for himself.
EDIT: Soneone pointed out that it's actually a gas can in Blonde's trunk, not lighter fluid. Which admittedly does poke a hole in my third point.