In comments on this post Martijn Faassen says:

Unfortunately, it has also meant that Zope is not as easy to scale down to small applications. Not being able to scale down negatively impacts the learning curve, and that negatively impacts adoption. We should fix this, and in fact work has been done on it. You're right in that the "hello world" case should be even easier (even though Zope's "hello world" does a lot more than you'd think at first sight).

I assume "Zope" in this context applies to Zope 3; Zope 2 has a funny learning curve. I don't know what a Z-shaped curve is -- I think that breaks my concept of a what a learning curve looks like -- but the curve is one that starts as being really really easy, and then really really hard. Zope 3 doesn't have a really realy easy part (which is fine, since that just led to false starts in Zope 2, IMHO).

But I'd say that Zope's scaling problem doesn't just hurt adoption, it really hurts development too. All applications start out as small applications. I could even invoke some hype word (maybe appending a version number) and say that the New Way Of Development involves lots of small interacting applications instead of large apps.

Good development in the beginning means deferring choices as much as possible and focusing on results instead of abstractions. Abstractions should emerge from your functional goals, and if you spend a lot of time modeling in the beginning then you've made premature choices and designed code that you don't yet understand. You haven't just wasted time, you've introduced a liability.

That doesn't mean abstractions are bad. I'm not saying we should all use PHP; sometimes it's faster to walk than drive, but using PHP is like living in a world where they haven't invented the wheel.

Zope 2 allowed you to start without modeling at all, but down that road led an unmaintainable mess (you can do maintainable code in Zope 2, but it requires up-front modeling in the form of Product building). Zope 3 encourages modeling from the beginning, but I don't think that's the right lesson to learn from Zope 2. It wasn't that Zope 2 was wrong for allowing that simple start, but that it was misdesigned so that there was too much of a disconnect between the simple form of Zope 2 and the reasonably-manageable form.

Anyway, there seems to be a lot Zope 3ers lately saying "hey, what about us?", so there's my $0.02.