It has been argued that if Article 50 was not committed to in the first 24 hours, then it is never going to be initiated.

various legal commentators beforehand were suggesting that it might not actually be this easy,  

 the UCL constitution unit pointed out in February that the wording of article 50 was that article 50 could only be invoked by the country, there are no provisions to expel a country (this had been noticed during the Greek crisis, but it would need a treaty change to force this through, and the chances of smaller countries ratifying the changes after seeing Greece  shredded by the banking crisis  seem somewhat slim.

The constitution unit argued that if the remain vote lost,  the only thing that could sensibly happen is that the prime minister not activate article 50, however they didn't see how they couldn't be forced to do this by the UK Parliament. Cameron by his resignation has sidestepped this, leaving the article 50 declaration for his successors

If a government attempts to make an article 50 declaration the next problem pops up,  an Article 50 declaration can only be made "in accordance with the countries constitution" Here we have an unwritten constitution problem, because there is no written rules then the  constitution is spread across multiple pieces of paper, One of these is the Scotland act, and there we have a problem, Scotland can refuse any changes to its legal system, leaving the EU would be a major change to the legal system so Scotland can say No.

The same problem appears to happen with Northern Ireland, although through the rather more indirect route of the Good Friday agreement. The EU is the Guarantor of various segments of the peace agreement,  several segments of the Northern Irish political system have indicated that there would be a legal challenge to any Article 50 decision through the constitutional courts.

Any idiot can face a crisis - it's day to day living that wears you out.