Possilbe the fuel pressure is bleeding down while the car is off. Does is start every time with just a couple of cranks? Never left you stranded? Does it do it more when you have let it sit for hours or overnight? Does it do it when you re-start it right after shutting it down? There is usually a check valve, pressure regulator, or a leak (injectors, among other places) that may allow the fuel pressure to bleed down while the engine is off. Maybe it's taking a few second while cranking to build back up.