It is a long time, but more than that, it is difficult to imagine. The chance of life developing by itself is indeed slim. Far to slim to be comprehensible by any human mind. But given the immeasurable amount of time that has elapsed in the universe, this event could have happened. Call it luck if you must, but we are here today for the very reason that we adapted to our environment.
Some individuals say that the planets orbit the sun too perfectly to just have ended up here.
But that is exactly what has happened. Everything that was not perfectly orbiting the sun either escaped the gravitational field or burned in the sun. The current planets just happened to be perfectly positioned so as not to be destroyed. The same thing has happened with evolution. Its genes will be spread more than the others in effect destroying the less perfect genetic aspect.