All are important. Which is most important depends on the position.
Although I would say that on average, at our level (rating 1800 and below) material tends to be the most significant in most games. How many sub-1800 players will seriously punish, say, the loss of one or two tempi?
Verywell put. :)
i would say at any high level its material but at under 1300 or so its develepment
1500-1700 is really tactics
I usually concentrate on material but im not that good?
Silman says, in this order
Which is the most important element to apply to your game? Developement, Material, Time, etc.