Thursday Evening's Life Altering Question

Why do invading aliens who seem to have spent years and years developing the most amazing technology, not find the time to quickly Google the word 'Earth' to find out if there is the possibility that the environment may have some startlingly harmful effects on them, or at least make sure that their super weapon/ship doesn't have a really easily exploitable weakness? Come on guys, if you're going to put all this work into spaceships and laser beams, you'd think you could spend 15 minutes on making sure you have a decent idea of the place you're trying to invade. Not that I'm complaining that I'm not a slave to an alien race. And yeah, I also realize all the invasions have actually been movies or novels, but I'm assuming it would play out the same in real life (just like how all wars or police encounters in movies are exactly like real life).