[eithed]

This might be an indicator that PM isn't doing their job; PM should be able to answer you questions regarding what the business wants (= people who you're trying to serve). Developers, by the nature of interacting with domain, do become experts in the domain, but really it should be up to PM what the domain should be doing business-wise.

[Jensson]

If that is what a PM needs then there aren't enough good PM to warrant a PM role for most products, so just make software engineers do that in most cases.

Edit: The main role of PM is to decide which features to build, not how those features should be built or how they should work. Someone has to decide what to build, that is the PM, but most PM are not very good at figuring out the best way for those features to work so its better if the programmers can talk to users directly there. Of course a PM could do that work if they are skilled at it, but most PM wont be.

[eithed]

> not [...] how they should work

So that we're on the same page, what I think should be PM responsibilities:

If I have a user story: "As a customer I want to purchase a product so that I can receive it at my address" - PM defines this user story as they have insight to decide if such feature is needed.

PM should then define acceptance criteria: "Given customer is logged in When they view Product page Then 'Add product to basket' button should appear", "Given 'Add product to basket' button When customers click on it Then Product information modal should appear" etc - PM should know what users actually want, ie whether modals should appears, or not; whether this feature should be available for logged users only, or not.

How this will work shouldn't matter to PM; these are AC they've defined.

Of course the process of defining AC should involve developers (and QA), because AC should be exhaustive to delivering given feature

[imperfect_blue]

The problem, in my experience, is that most PMs don't add anything when it comes to drawing up the acceptance criteria.

In your example of an order placement - the PM has no special knowledge of what is a good customer order flow. Developers are usually way better at coming up with those by the dint of experience and technical knowledge of the current codebase and make the appropriate speed/polish trade-off.

PMs acts as an imperfect proxy for what the customer wants, making judgements off nothing more than their own taste. And though there are many great PMs, the taste of a PM is usually worse than that of developers and designers on average.

IMO the main business reason they exist is for organization accountability and ownership, despite the often negative value they bring.