Pennylane (France) Junior Ruby On Rails Developer interview questions

I had a few rounds of interviews and a homework to do which consisted in building an app that returns recipes based on the ingredients you input. I passed the majority of interviews but failed the last one with the management. I had that interview on Friday, on Monday I received an email from the HR asking me if we can schedule a meeting to discuss the last interview, so he schedule it for Wednesday. I got my hopes up because I thought that if they reject me they will just send a simple email, but I was wrong, I got rejected because the interviewers believed the cultural gap it's too big.