I would LOVE to get my 2 hours back in a day because of a last minute interview cancelation. The only person who would be truly irritated is the recruiter, who's job depends on meeting candidate quotas. Even then, they want you to be successful.

Trust me anyone reading this, if you are not feeling well, or something is distracting you, please, please, do feel free to reschedule your interview, even last minute.

Once you go through the process, and it's a no-hire, that is recorded in the system and you won't be allowed to try again for some extended period of time. At my company, it's 1 year.

The obvious counter to this is: Which will give the worse impression: Canceling for a good reason or showing up and being distracted and performing poorly? Companies like the usual FAANG are nice enough to merely give you a 1 year embargo. In other companies I've worked at, you interview for a team and if you do poorly, the team will simply never interview you again (although you could interview for a different team at the company).

Also: Do you really want to date someone who doesn't care that your cat may have a life threatening problem?

Finally, even if it's not that serious (cat emergency): Do you really want to work/date someone who is that susceptible to this bias? I know it's the norm to fall for first impressions, but for me, it's also a signal of problems I'll have with them in the future.

BTW, my cat had a serious health problem once. She needed lots of immediate care for a few months (at home, away from work). And the vets were telling us that even if she got through it for now, it will come back soon and we should really consider euthanasia - the condition would eventually kill her - not many cats would last a year with it, and chances are her she would be in pain for much of it.

And this all started a few days before I started my new job.

I went straight to my new manager (before my official start date), and explained to him that the cat was my priority - I could take a leave of absence or whatever was needed, but I needed to figure this out (either euthanasia, or time off for treatment options, etc) and could not be anywhere close to 100% at work.

Fortunately he was sympathetic and said I should not worry and do whatever was necessary.

The job turned out to be crappy, and I stayed there longer than I should have entirely because of this.

For a small company it matters, but for a FAANG interview the person rescheduling your interview is completely disconnected from the people making the hiring decision so it would literally not make a difference.

I rescheduled the second date with my now wife at the last minute. Worked out well for us, but I was so tired from work that there’s no way that date would have gone well (busy period of a project at the time).

It doesn't give a good first impression, but failing miserably is somehow even worse...