Cisse can set someone through 1-on-1 with the keeper, if they score he gets an assist, if they miss he doesn't, neither of those outcomes affect Cisse's actual contribution. On the other hand Cisse could roll the ball to Hatem 40 yards from goal who then precedes to skin 2 players and rifle in a thunder bastard, he gets an assist for that, if Hatem was to skin 2 players and then hit the corner flag he doesn't. It's a pointless number on it's own and simply saying "He only got 3 assists!" means very little.
Fwiw I don't think he's the most creative striker out there, far from it, and we would be better off with many other a player when he's off form and not scoring goals.