They split the country into arbitrary plots of land which each get to elect one member for the national parliament. It used to be even worse, with the plots of

They split the country into arbitrary plots of land which each get to elect one member for the national parliament. It used to be even worse, with the plots of land having no consistent size (with some of them having a population of 1). Rather predictably this means the number of votes a party gets has no relation to the number of seats they get in parliament. Since the number of seats per party is far more important for the political course than who gets elected for each party this is undesirable. This gives weird results like the Scottish nationalist party getting 3.9% of the vote and 48 seats, while the libdems got 11.6% of the vote and 11 seats.