I've worked with startups and non-profits in Canada, Hong Kong, and the United Kingdom. Projects include Hong Kong's first social accelerator, the i2i Program, TEDxYouth@HongKong, and International Development industry events in London.
No. If anything, sometimes it is better to have the time constraint, as it forces you to build an efficient system to save you time. In addition, it forces you to truly spend time on the things that matter for an MVP and refinement.
My examples would include: 1) a portfolio company where the founders had built their game-changing business in a year and automated their system to the point where they only had to spend 1 hour a day after work on it and the occasional few hours on weekends. 2) an advisor whom is full-time at an international consulting firm and has 2 lean startups that have attracted investors