I agree OP- the general lack of competence or effective leadership makes them look so amateurish. There lack of effective opposition is letting this government get such an easy ride. All governments, of whatever political persuasion, need an effective opposition to hold them to account.
The budget was a prime example. Osborne made a u-turn on tax credits, found money to spend on police, military etc from the OBR change in forecast (and if this turns out to be wrong, he could be in trouble) after claiming the country couldn't afford it previously. That should have made it so easy to give them a rough time. But did labour manage to do that? No! Why- because McDonnell decided to try the Mao "trick"- it was so predictable that this would backfire and could easily be misconstrued thus overshadowing anything else he had to say, sensible or otherwise. Yet, McDonnell did either not have the political nous to understand that or decided petty point scoring was more important. Added to that, the way Corbyn arrived late- just before the chancellor started talking- seeming very non-plussed by the whole event, it just does not inspire confidence.
Or take Corbyn having to clarify that, yes in the event that terrorists were on British street(s) attacking people he would accept the police shooting to kill to stop that. I find it incredible that he could not be coherent enough to make that clear the first time he made a statement about it. He needs to start thinking before speaking.
The mess they have got themselves in over the potential of intervention in Syria is yet another example of the ineptitude. I understand that when he met with the PLP to try and hammer out a party position on this matter he simply read from a statement and then left, no discussion and no attempts to actually persuade the labour MPs at that meeting round to his way of thinking. That is not leadership. Then the next thing he issues that letter, which just caused more strife rather than settling things down. Meanwhile his deputy and shadow defence secretary openly disagree with him and then his side-kick McDonnell says they "probably" will allow a free vote after all. Chaos reigns again.
I accept that Corbyn has a grass roots following, and was voted for by a ledge majority, which does give him a mandate but he needs to speak with and for the whole party not just those who agree with him. He needs to persuade people of his way of thinking, not just engage with those who already agree with him. If for no other reason that a percentage of non "corbynites"/Labour supporters will need to be persuaded that he is capable of being the next prime minister and the party have policies which they can agree with. That includes a lot of floating voters, like me, who have no particular allegiance to one party.
At present Corbyn is not inspiring me to have confidence in him. Nor are many of his key supporters. I think a number of Corbyn's policies are downright barmy. I won't vote Tory as things stand, but I definitely won't be voting labour either while this lot are in charge.