Red Flags all over in the 3rd interview! Read below and ask yourself if this is the work culture you are looking for.
1st + 2nd interview: friendly and easy chat to 2 recruiters and the owner, who seems to be a nice person. His software is also pretty impressive, it has great value and will drive great revenue. Interview questions were very easy, however a bit generic. Could have been a bit more individual, as I am not sure that they really got to know me.
3rd interview: I prepared for a demo which was supposed to go 20-30 minutes. I did manage to finish it but only with great difficulty. This demo was the worst in my entire career and the interview was the worst I've ever had. Why?
Because there, I met my future manager, who was blatantly rude and abrasive with me. He did not let me finish my sentences, interrupted me all the time, did not like my answers and disturbed my presentation. He questioned things I had no control over (that all companies I worked for did send out a quote after discovery, so before the demo, to ensure the lead has the funds (which we qualified via BANT)). In his opinion, this was garbage, and he did not hold back to tell me about it.
Icing on the cake: he did say in front of everyone (owner and recruiter were there, too) that he does not care about education or work experience, as "you can work for years and still know nothing / be an idiot".
That is all that you need to know. If education and experience don't matter to you, why did you look for someone with a degree and years of experience? Exactly. They aren't looking for value as it seems, they are looking for a disposable person who can be anyone really, as they will probably not keep you on long enough to care.
On confronting the in-house-recruiter after the interview, I asked directly if this was a "planned act" in terms of disturbing the interview to see if I work well under pressure (it is Sales and Finance, would make sense), he declined. Just to say before we hung up "He might have done it to test you". I was speechless.
In my career of almost 10 years (Sales & Finance), I never came across someone so abrasive, rude and disrespectful ever. The fact that the owner approved this behaviour without intervening tells me that this is the culture you have to accept: a toxic one where your work experience, education and you yourself as a person will be not valued at all. Good luck!