Five-year election cycle, and the dominant party is very good at controlling the narrative
Selling public infrastructure lets you give tax cuts now, and you'll be long gone before people recognise that they are paying more and getting less. It's much like MBAs making cuts - you can boost the bottom line in the short term and be gone before the blame starts gathering
We have a fptp electoral process, which means there are a lot of safe seats in parliament. In battleground seats, a vote for the third party is effectively a vote for the first. People who want not-the-incumbent cannot choose which party they actually do want. I personally have been disenfranchised all my adult life, MEP votes excluded. (If I could change only one thing, I would abolish fptp.)
Moreover, like most populous Western countries, most of the electorate is not well educated on politics or economics; they get their political news from limited sources, and they don't seek information that challenges their prior beliefs.
These facts combine to reduce electoral accountability.
Having flogged the public infra, renationalisation is tricky. You either buy it back at market value, which means imposing a tax burden and playing into your opponent's electoral strategy, or you seize it and spook capital markets, which also plays into your opponent's electoral strategy.