That depends on what you perceive your future to be... Maybe if you are have found your self in a situation that despite all your best efforts you were forced into and there is no way out, that your life is no longer your own, that any perceived future is one in which you see nothing but further pain then no that's not laziness (whether that is justification to CTB or not is another thing).
Maybe you can't face the idea of simply living, that its too much effort to continue then that is most likely depression. I find it very difficult to think that someone would have a real desire to CTB simply because they were too lazy. If someone were contemplating suicide just because they couldn't be bothered then I can't believe they would ever be bothered to do it. Everyone at times have said something along the lines of "Meh, why don't I just kill myself then I don't have to worry about all of this rubbish" but I can't imagine a world in which they would then do something as severe as then commit suicide without some real underlying problems.