On the other hand...
Mars has turned out to be a lot more interesting than we thought back when the first probes showed something that looked more like the Moon than anything else. Then there are the moons of the outer planets, and the atmospheres of the outer planets themselves, which may have more potential than we think.
Life needs molecules and energy, and the universe has plenty of both. We might not find ancient ruins of lost civizations in our Solar System, but that critter hopping past a camera, or more likely, something growing in a probe's laboratory, isn't completely out of reach.