It's a big conundrum:

• On one side, most people when told actual policies which are generally considered left-wing (say, Free Education) agree with them
• On the other side, most people don't have the attention span to read long lists of policies (hands up anybody who ever read the entire electoral program of even just one candidate in an election they voted in) so even the most well-intentioned politicians end up using short political terms with vague-ish definitions which are easily subverted, to describe their own set of policies or those of others.

So we end up with Liberal this, Socialist that and if you try and get down to tightly defined nitty-gritty details of their meaning, no two people fully agree on the definitions.