Such as what? I hear UKIP demonised a lot, but I genuinely don't know of anything they've done that is bad that wasn't simply political disagreement (wanting to leave the EU) or talking about contentious issues in a clumsy and ham-fisted way (immigration).
Failing to present a coherent, workable programme for how we'd leave the EU and at what cost is leading us to a situation where the government is doing civil contingency planning as if we were going to be hit by a hurricane rather than a self-inflicted disastrous choice.
Disclaimer I am a remainer and dislike UKIP as much as anyone.
And also the entire immigration discussion was some bs considered the non-EU migration is been higher than EU one for decades https://fullfact.org/immigration/eu-migration-and-uk/
https://www.theguardian.com/politics/2016/jun/16/nigel-farag...