@Byllis it usually comes out before that. At offer / reference stage. People either panic and fluff when they are asked for references or they don't say anything but their referee does. At that point, I've had a few incidents where it has become an issue.
One notable one was a guy who was a really, really nice guy but he didn't tell me or my client that he'd been working in a different sector for about 8 months after his "most recent job". My client found out when he was taking a reference and the referee gave him an ok reference and conversationally said, "how's he doing? Was was working at (xyz) last I heard."
My client (rightly or wrongly - don't shoot me - I'm not him!) felt really uncomfortable. Not that he'd been working in a "lesser" sector but that he'd spent over 3 hours with him over 2 interviews, they'd also talked about their respective families, hobbies their girls shared, the state of the job market and he'd never mentioned it. It put him off him completely. He felt he'd been lied to. He pulled the offer. Believe me, I did everything I could to mitigate it (In my interests as a recruitment consultant) but he wouldn't budge. Just maintained, why did he not just say so?
I've had people panic when their new employer has sent for their P45 in the past and the "latest employer" had already been asked for it by another firm.
Not everyone is an FD. Not everyone is able to style it out either! People make situations much worse when they haven't been honest.
I can't quite believe I'm having to justify not lying to a room of adults.
My experience now, it that employers aren't batting an eyelid if you're working in Tesco. If your prev experience is relevant then it's being taken as that.
I think it's also worth mentioning that in 09 recession, quite a lot of my hiring clients lost their jobs and took something to tide them over. Most that wanted to managed to get back to where they were over time. Don't give up hope.
Also worth mentioning that if you are, say, an accountant, you're not as vulnerable because you can move industry confidently. Still as an accountant. As an 'industry specific' professional, that's different and relies on transferable skills, which can be difficult in a job short, candidate rich market.
Keep going folks. It's getting better every day out there, job wise, if you're not looking at hospitality, travel, treatments.