nope, they're often different... but the question is why?
Design - it could be built into the frag, example it's loud and then dies because it's poorly designed or cheap, or maybe it's an Eau de Cologne so it's meant to fade out quickly after a burst of smell
Application - the wearer dabs/rolls it on instead of spraying it on, so the scent takes longer to evaporate but doesn't project as far, or they spray overly liberally so it lasts all day but only because they put on so much,
skin type - for some people, the same application has different results. I have dryer skin so frags tend to not last that long on me for example.
Concentration/carrier - EdP's and oil based frags tend to project less and last longer