Alternate Character Interpretation: A popular fan theory basically goes, "George went to the future to interact with the peaceful, future humanity - and he destroyed it". The Morlocks, while monstrous looking, are the only one of the two decedent races of humans to show societal intelligence by domestication, preserve of old technology; and are coming up with a civilization of their own after ancient humanity blew itself to bits. The Eloi look pretty by human standards, but show very few degrees of sentience and are as dependent on the Morlocks for survival as something like domestic cattle and pigs are to humans. While George does go back to try an educate the Eloi, how effective that is going to be could be entirely fruitless given their low intelligence. Yes, the Morlocks did attack him, but only after he invaded their home and happened to look exactly like their primary food source. But because Weena and the Eloi are dumb but pretty and the Morlocks are smart but ugly, George kills the latter for the former. What Measure Is a Non-Cute? indeed!
There was a literal special-effects failure on the set. The day before the crew was set to "destroy" the London of 1960, they made a huge batch of oatmeal, which would stand in for the lava flow. Unfortunately, there came a very hot day, which caused the oatmeal to ferment! It no longer had that thick consistency, but the effects team had to just roll with it.
Another real life example had Alan Young commenting on his make-up as the aged James Filby failure:
"They made a face mask of me to fashion all that rubber stuff — the old age pieces — all around. On the morning of that shot, I got made up by Bill Tuttle, and as I left, he gave me a little jar of glue, and he said, 'That's in case it comes off,' and I said, 'Well, won't you be on the set?," and he said, 'No, the budget can't afford a makeup man on the set.' So, I had this jar of glue, and that was at 6:00 or 7:00 in the morning. Well, they didn't get around to shooting that scene until late afternoon, and by then I could feel bits of my face falling off, so I'd get the glue out and stick it back on again, but by the time they actually got around to shooting that scene, it was about 4:30 or 5:00. So George said, 'Alan, I can't do any close-up's because I can almost see the glue brush strokes on your eyes.' So, if you remember the scene, it was done in a two shot all of the time. There were no close-up of this old man because bits of the face were peeling off."