Did some research for you Jimbo and here are some possible reasons..

Whilst Labour were in Government he rebelled over 400 times against his own party's whip
He regards some members of IRA and Hamas as friends
He and his Momentum supporters are a throwback to the socialism of Derek Hatton where taxi drivers in Liverpool were sent to deliver redundancies to council workers.
He lacks true leadership skills.
He would ( it seems) never take us to war even in defence as he is an avowed pacifist.
He has singularly failed to actively tackle anitsemitism and misogyny in his party.
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Took me about 5 mins in a Google search. NOTE the above is not necessarilly my view just those that came up on Google.
Thank You

Posted By: Basingstoke_Canary, Apr 26, 12:53:47