Sadbutdru

Bloody small cylinders, always getting stuck in things!

Or "if you think the reason for the result is not correct" could cover it.

Yeah we used to imagine a future where all the household tasks were done by robots, and we humans busied ourselves with intellectual work (e.g. The Jetsons).

But as it turns out, generating text and computer files is relatively easy for machines, but physical robotics in uncontrolled dynamic environments is a tough problem.