EFTA, the European Free Trade Area, was created in 1960. This was after some countries, like the UK, were excluded from the negotiations by the 6 original countries, which formed what is now called the EU !
The EU has changed a great deal since then, but has been stumbling in recent years ! This has climaxed with the arrival of countless desperate Refugees from the Middle East and other Migrants, from all over the world, all seeking a better future.
The unexpected Brexit vote in Britain has in fact thrown the spotlight on critical shortcomings in the EU. The EU has not updated its basic principles in spite of the Middle East War and the Refugees. Neither Frontiers, nor the Freedom of Movement are efficiently controled ! The reallocation of surplus Refugees by Merkel, was the last straw !
Smaller countries in the EU are watching Brexit closely. Several were originally in EFTA, which is purely a Trading Club ! They may now be tempted to "exit" the EU and rejoin EFTA !