The UK Visas and Immigration, as part of their decision making process, will carry out a credibility assessment to ensure that the Innovator visa applicant genuinely intends to undertakes work relating to and implement the ideas set out in their business plan.
You must, therefore, satisfy the UK Visas and Immigration, on the balance of probability, that you are a genuine Innovator Visa applicant and will spend the majority of your stay in the UK developing the ideas stated in your business plan.
The UK Visas and Immigration will only look for factors that may give rise to suspicion that the Start-up visa application may not be genuine. Those factors include, but are not limited to previous refusals because of genuineness concerns or there having been a significant number of identical or very similar applications in the past, some of which have proved not to be genuine.
In practice, however, the UKVI will not carry out a very rigid assessment as the endorsing, that issued the endorsement letter, would have already carried out its own genuineness test.