What I intended to say is that it's difficult to differentiate one consultancy from another. You have to do that based on clearly proven, previous performance. When you're starting a new company, it's easier to sell something that's new (like a service or product).
I don't understand the point you're trying to make. It is just as hard to differentiate a product as it is to differentiate a consultancy. And there are far more differences between consultancies than "experience".
This thread is about open source software. My point is that it's easier to differentiate open source software from other open source projects than it is to differentiate a consultancy from other consultancies.
The reason is simple: a customer can try out an open source project for free.
And then they can hire the people responsible for the Open Source project.
That's kinda the point of Open Source as a marketing tool. If someone sees how awesome your Open Source software is, and they want more of that same brand of awesome (but to do something just a little bit different), they know exactly where to go.
I just talked about a software services business that I worked with a few years ago called Enthought, and it's deeply relevant to this threads interest. While at University the company founders built a set of Open Source Python (and Fortran and C++) components for scientific computing. They then went on to start a software services business with a little bit of money raised from family and friends. Their revenue is now in the millions (I can't be specific about how many millions, as I haven't known with any specificity for many years, and I've never been told that they would want me to talk about those numbers with specificity). Their business has very frequently first come from customer exposure to their (deeply awesome) Open Source software.
What I intended to say is that it's difficult to differentiate one consultancy from another. You have to do that based on clearly proven, previous performance. When you're starting a new company, it's easier to sell something that's new (like a service or product).