This question seems like a simple one at first, but considering all the variables it is tough to answer outright. "Is the bike hot?", "Is the bike cold?", "Has the bike been sitting for several weeks?", "Is it carbureted or fuel injected?", "Was it just tipped over?", or "Was the float bowl just drained?"
In my opinion, each scenario I've questioned above invokes a slightly different answer. Combine this subjectivity with one's own personal starting routine and the ease of which the bike will fire up, the bottom line is it's going to be different for every rider.
As a rule of thumb, if my bike takes more than five kicks to fire up as time progresses I will begin investigating possible starting issues.
"What things might make a bike hard to start but not necessarily mean the engine needs to be torn apart?"
On most bikes there are two or three things that adversely affect how well the bike will start. On carbureted bikes the pilot jet circuit controls fuel flow from idle to about 1/4 throttle. The pilot jet has a very small orifice and clogs pretty easily. Once clogged the pilot jet is ineffective in delivering the necessary fuel to the engine and starting the bike becomes extremely difficult.