Priorities Ignored

I Have found this to be true as well, this is fairly frustrating. I just rebuilt these Water Purifiers after they weren't prioritizing them, and they still will not fill them at 9. This is with plenty of Dups and waiting until almost all other tasks are complete (I rarely prioritize, I think they only high priorities on this playthrough at the massage tables.  Don't know what to do, I need to Purify more water at once, I want my second Pump system going! 

It gets especially frustrating when they just...build priority 5 tiles instead of a priority 9 biodistiller that's been sitting there waiting for twelve cycles that they desperately need because they're running out of air and they just. Won't. Build. It. 

 

SCREAMS

the priorities for delivery have some problem, some time they dont go for priority 9 jobs, if they are delivering.

I've had issues where I deliberately stop any and all other tasks either by disconnecting the machines, or cancelling the pending builds, and leaving the dupes nothing whatsoever to do but what I prioritized them to do, and they will just stand there idle instead.