Sometimes we find ourselves in a position so incredibly bad - so apparently insane, in fact - that we can't understand how we got from Point A to Point B. The reason we can't understand this is that Point A was something as simple as "I'd better get out of bed now", while Point B is something as strange as "I guess the only way out of this is to take my Doomsday Machine into a near solar orbit, and then heave it into the Sun."
If you were to wander into this story at Point B you would decide that Lew was a madman and probably deserved everything that was coming to him, with the unfortunate corollary that the Earth would also come to an end. But life is just so much more complicated than that.
It's possible to go from Point A to Point B through a series of slightly bad decisions. On the cusp of each of these slightly bad decisions you look around, see that you're in a bad spot, and choose an option. The option that looks best in your situation may be just a little bit bad; but all the other options look even worse. If you choose the slightly bad option over and over again you find yourself in an ever-worsening downward spiral that has no apparent end except, in Lew's case, the end of everything.
This whole process is well documented in Frakenwiler's classic How We Got From Here To There, And Why We Shouldn't Have. Frakenwiler's conclusion is that a sequence of slightly bad decisions comes down to the conflict between two old adages about money.
If we look at our bad options and choose the worst one because, really, it's only a little bit bad and (who knows?) it might even work, we are telling ourselves that 'In for a penny, in for a pound' applies to our case. We decide to go a little bit more wrong in an effort to make things right.
If, on the other hand, we ask ourselves whether it makes sense to 'Throw good money after bad' we have a chance to get out of the cycle and stop making things even worse, not to mention putting a little something by for our retirement.
Of course this doesn't always seem practical: if Lew got out of the cycle now the Earth was going to be eaten by his experiment. So Lew (like most of us) threw his pound in with his penny and headed for the Sun. We shouldn't judge him too harshl