Saw those lines today, somewhere else, AKA borrowed a few sentences, from the OP's experiences, confirming they are valid here as well, at times, as I is on so-called retirement extensions for a decade, and had several examples, too early too late to extend, let you sit and wait on a chair, even the paperwork is done, and they're all chit-chatting personal unrelated matters, missing unlisted items in the pre-checklist, bedroom pic with wife no acceptable blah blah OKAY - have to add, most at times sailed thru the process super smoothly
One of the most unpleasant parts of the process used to be the vetting of one's paperwork before being granted a queue number for an appointment to see an Immigration Officer. This process used to be conducted by bureaucratic harpies who appeared to be adhering to a dictum of "they shall not pass" whatever the circumstances. Any failure to dot all the i's or cross all the t's brought down withering scorn and instantaneous rejection.