They either randomly turn into killers or get their comeuppance after their one plot ends.

A few of my favourites below.

Alan Bradley.
Jim McDonald.
Charlie Stubbs.
Mike Baldwin.
Richard Hillman.
Tony Stewart.
Tracy Barlow.

Phil Mitchell.
Grant Mitchell.
Archie Mitchell.
Michael Moon.
Dirty Den Watts.
Nasty Nick Cotton.
Chrissie Watts.
Janine Butcher.

Carl King.
Cain Dingle.
Eric Pollard.
Steph Stokes.
Sadie King.
Kim Tate.
Charity Macey.
Chris Tate.
Matthew King.

Warren Fox.
Claire Devine.
Silas Blissett.
Mercedes McQueen.
Justin Burton.
Doctor Paul Browning.
Niall Rafferty.

Paul Robinson.
Izzy Holand.

Barry Grant.

J.R Ewing.

I think both Vincent and Gavin in EastEnders are quite interesting. We don't really know what is going on with either of them, and I'm looking forward to finding out! (Although I'm not convinced whether Vincent is actually a proper baddie or an undercover cop)

Coronation Street does not have any villains at the moment, especially with Tracy and Tony calming down recently.

Emmerdale has had a few for me this year with Robert, Aaron, Ross, Jai, Rakesh all coming across as villains.

Psychopaths like Gavin and Archie in EastEnders are fascinating to watch even though you hate them. I prefer the more sympathetic multi layered villains who show guilt and remorse like John Stape and Tony Gordon in Coronation Street, but you can find something interesting about most villains.

Gavin does interest me. Dean is messed up. Ross I can't take serious.

Baldwin and Jim McDonald were not villains

Oooh I like this!!

Jim certainly is and Mike Baldwin was considered one in his early days.

Flawed but not villains ...

Home and Away has a very interesting villain at the moment, Charlotte

I agree.

Matter of opinion.

Villain in Mikes day was something totally different.
Dennis Tanner was the shows first "villian."