Why tho?
Cloud initiates contact with Zack about escaping, who then replies with the suggestion of doing at feeding time when their pods get opened up. Surely this means they were both at the very very least conscious at the last feeding time to know that that's a thing, and potentially the hundreds of feeding times they've had before that.
eye-dee-kay, d00d. I suppose I'm thinking, ''They have been confined and worked on for five years.'' which is a long time, indeed, to be kept captive. Why haven't they been able to escape before? Surely they would've tried if they'd been relatively conscious and able to communicate? Surely that would've taken precedence over, say, chitter-chatter over the weather or how badly Hojo's shoes clash with his overalls on any given day?
So I speculate that the reason why they didn't escape is that they were unable to. Why? I assume that their being heavily monitored would be a factor as it seems a very natural step (to me anyway) that Hojo would take such precautions when confining two men of impossible strength who have every incentive to kill him. Like, surely, he wouldn't want to give them too many opportunities to be able to communicate any sort of plans to each other? Surely any of the assistants that Hojo (might've?) kept around or the man himself must've noticed some alterations to their environment, like messages being scratched on those very permanent (thus unable to erase lmao) glass pods?
Maybe he was cocky and didn't give a shit––that doesn't sound totally out of character for Hojo. I suppose he had reason to feel complacent at some point considering that he managed to keep them confined for all that time, that self-satisfaction giving way to laziness, the laziness presenting opportunities for Zack and Cloud to properly plan an escape because those silly smug billies overlooked something––like plans being scratched onto glass lmao.
Having said this, this is all absolutely conjecture on my part and I realise that—as far as I know (and I'm far from being a specialist on the compilation of ffvii whoopsie doo) we haven't anything detailing the exact going-ons in that basement, do we? If so, LMAO I JUST MADE A TOTAL ASS OF MYSELF WHOOPS, but if not... that leaves me with my imagination and that's what I imagined. ¯\_(ツ)_/¯ Hope you get where I'm coming from! ʕ•ᴥ•ʔ