I started a PhD program few years ago. My first PhD supervisor decided he wants to quit university and stopped supervising PhDs (he was 70 years old). I lost about a year trying to convince this supervisor to continue, and another year trying to find another supervisor when he quit (he pretty much left all his PhD students in the air).
I transferred to another university, but nobody counts the missing years and I should finish in few months. The condition put by my new supervisor in order to be allowed to present my thesis was to come up with at least 2 new contributions in addition to my previous contributions (I have published some papers with some contributions, but many of them were group research and this supervisor said that only 2 or 3 of them really count as mine).
Now the problem is that during the last year I have worked a lot both at the university and at the PhD, but only during last weeks I started to have some ideas about what these new potential contributions could be. Considering the lack of time, there is a high chance that I won't finish on time (due to the regulations from this country you have to finish in 5 years, nobody takes into account the fact that you lost several years with other problems like replacing your PhD supervisor).
I'm not a lazy person, but first time I really had no luck, and with the second supervisor it took me a lot of time to play in the league he wanted ... Basically all articles discussed with him about Machine Learning were from MIT, Carnegie-Mellon, etc. Essentially I had to spend about a year and a half to get my knowledge to the level where I can design new algorithms or create new things that would get accepted to top journals reviewed by people from these institutions.
Of course, I can register again for the PhD, take the exams again, and present my contributions in a new thesis. The problem is when I will add all these years it will result a large interval for Europe: 7-8 years, instead of 4-5 years. My question is this: how will a potential future employer from both Academia or Private Company look at this time interval? Is it ok to try 2-3 times to finish your PhD? Will the fact that it took to long finish the PhD affect my career?