To give (an utterly ridiculous) example, the irish government copied a model of university funding from the UK. Now there is one major difference between the two systems. In the UK, the government controls the number of university places, while in Ireland, the universities do. The department of education rammed through this new funding system that divided up money based on the number of students per discipline (arts, science, medicine, business all having different modifiers). Now, this system worked in the UK as the universities couldn't increase their places themselves, but caused a lot of problems in Ireland.

Trinity College had a strategic goal to stay the same size as they were for undergrads, and increase postgraduate intake. When this funding model was introduced, they then had to increase UG numbers or lose loads of money (as the amount allocated was fixed, and other universities were expanding).

I think its a more general problem though, politicians are hesitant to try anything new as they can be blamed, which leads them to copy solutions that appear to be used elsewhere, as they can then blame the other country.

And the proposed post code system (which they occasionally talk about introducing) was going to just be a copy of the UK system instead of learning from the mistakes.