What are the Disadvantages of Specialisation?

-Workers doing Repetitive Tasks leads to Boredom -Nations become less Self-Sufficient and more Reliant. If Trade suddenly becomes negatively effected, for say Oil, then Nations who Import a lot of Oil will struggle a lot -Inflexibility can be setup - for example when the Mines shutdown, it led to the Workforce having only Non-Transferrable Skills. In other words, Structural Employment across North England and Wales.