One often finds participatory democracy presented as taking a relativistic "will of the people" as its ideal, in contrast to the more "principled" rule of a managerialist elite. But this confuses outcomes with methods. It would certainly be a mistake to say that the right result is whatever follows from a popular vote. It would be just as silly to define the right in terms of whatever the managerialists happen to prefer. Normative politics is surely not so arbitrary. We should understand "right outcomes" as an independent ideal. The question is who would most reliably pursue it. Should we invest decision-making power in a few flawed politicians, or distribute it more evenly amongst the populace?
This question may also be conflated with that of the scope of political power. Unrestricted mob rule is often presented as an alternative to liberal constitutionalism and individual rights. But what has that got to do with participatory democracy? Giving absolute power to elected politicians would be silly too, but no-one takes that as an objection to managerialism. Perhaps the problem is that some demagogues actually advocate unrestricted populism. They should be opposed, along with anyone else who would seek to strengthen political power over individuals. But their position shouldn't be confused with participatory democracy itself.
So there are three political axes to distinguish here. The first dimension concerns the objectivity of right outcomes, or 'what' to do. The second concerns the rightful scope and strength of political power. Finally, we can ask about the distribution of that power: the question of 'who'. This, I suggest, is how the democratic question should be understood. It's merely about who should wield power, not how much power they should get, nor what they ought to use it for. Those are entirely separate questions.