Assess the advantages and disadvantages of retaining the first past the post (FPTP) voting system

The advantages of the existing first past the post (FPTP) voting system used for British elections include a higher likelihood of producing majority governments than proportional voting systems such as STV and the simplicity of having a system that only requires one vote rather than a ranked or weighted system. An election result that produces a majority government means that governments are more able to effectively pass legislation through the House of Commons and therefore generally have greater power to enact legislative change than coalition or minority governments. This is beneficial as in theory the electorate are more likely to see manifesto pledges enacted. Meanwhile, a simpler voting mechanism removes the potential time or effort barrier a more complex system might create and as such helps increase voter turnout and by extension, the mandate and legitimacy of the elected government.
On the other hand, the disadvantages of FPTP include its tendency to inflate the success of the largest party to the detriment of smaller parties. It also encourages tactical voting and exacerbates the phenomenon of 'safe seats'. While FPTP is good at producing a strong government (although this has been proven to be less the case in recent years), in doing so it can also place in government a party with a 'majority of seats' but actually only a plurality of votes. In other words, more voters actually didn't vote for the party in the election than did. This brings into question the legitimacy of the government's mandate and the extent to which the British system can really be considered a 'representative' democracy. One of the side effects of using FPTP within constituencies specifically is the phenomenon of 'safe seats' and 'swing constituencies' where voters are technically free to vote for whoever they want but are in reality strongly limited or disenfranchised by the strong bias the system creates towards a 'plurality' of votes. This means that voters will often be encouraged to vote for one party in order to keep another out rather than actually voting for who they ideally want to.