I interviewed for a startup by one of the two co-founders to whom I was introduced to through a mutual colleague. This was around 5 weeks ago. After an interview I was told that I would be a good fit for the startup and would receive my offer letter within a week but I still haven't received the same. The startup is in its early stages with less than 10 employees and have just raised their seed round. Upon contacting the co-founder I'm just told by him that he's really busy and will send it across as soon as possible.
What I wanted to know was, whether this was common in the case of a startup or does it reflect something else like they made a wrong hire and are just trying to delay the rejection (maybe because he knows me through a mutual colleague) or I'm not required any more.
Even if the offer letter does come through, how much weight should I attach to this delay in making the decision to accept or not considering startup founders are actually quite busy.