Order Placement Issues

[DrBeardface]

So I'm currently running 7 different MT4 terminals, on different accounts, with the same code, only with different parameters to try and optimise my strategy. I accidentally loaded the same parameters into 2 of those terminals, but couldn't be bothered to go and change it. I just assumed that I'd have the same results on two of the simulations I'm running. However that is not the case. Even though they are running the exact same code they seem to be placing different trades. The difference isn't massive, but i'm curious as to why there might be a difference at all. Any ideas?