You can get to a level where a shot is successful from a technical (in focus, proper exposure) and basic photography (rule of thirds composition, level landscapes etc.) level rather quickly, particularly on digital where the cameras can do a lot for you.
Getting successful shots from an artistic perspective is an arms race between your increasing discernment of what makes a good photo and your ability to push yourself and raise your level to at least trail the former.
In other words its hard and tends only to get harder. But success tastes sweeter too.
What shall we say about Gary Winogrand then?
'He had an insatiable urge to be out and about, photographing life around him. In total (on the low end) we can be certain that he shot at least 5,850,000 photos in his lifetime.'
Pretty sure most of us saw maybe a hundred or so of those. On film too...