If I were handing out letter grades for space probes and landers, they'd get a C on this one (maybe C+ if they somehow manage to get significant payload data back over the very low-bandwidth link they've been able to establish). Why? Well, first of all, they actually made it to the moon rather than stalling out in orbit or wandering off in the wrong direction. Secondly, the probe soft-landed, rather than plowing a new crater and spreading parts all over a kilometer radius, and it was in good enough shape to phone home. They got two out of three of the most important things right. Now they just have to work on keeping it upright on the way down.