Not alone for a single iteration, no, but it's a self-feeding process. The existence of mass producers necessitates the existence of mass suppliers and mass markets, and the more massive any one of them is, the more massive the others must become. If you have a mass market (for instance, a government in a war needs food, oil, vehicles, and explosives in large amounts), you need mass producers. For mass producers, you need mass suppliers of the raw materials. They in turn need mass suppliers for their own raw inputs. And when it eventually turns out that there actually *isn't* a mass market, there's a crash. The crash is the best illustration of how it works because it happens more suddenly. A couple major producers cut staff and capital because they can't sustain their output profitably without a market to sink it all into as they thought there would be. Their suppliers then have to cut staff as well, as do theirs, and in turn theirs. Then there's less employment and less consumption, leading to a further worsening of the situation. Austrian business cycle theory is basically the financial aspect of this.
The entire mass production/consumption economy is a symptom of the problem and a problem unto itself.
All I'm saying is that it's more efficient in the long run to produce things at small scales for local or small markets with general-purpose tools. It may not be more efficient strictly in per-unit cost, but it cuts out most management and most distribution overhead and makes it easier to repurpose to rapidly changing needs when those needs arise, and reduces any incentive to overproduce things people don't want in those quantities thinking you'll recoup the costs of overcapitalizing with reduced unit costs.
I recognize the ways that firms and mass production can be more efficient, but do not believe that those factors have as great an effect as you probably do. As long as you also recognize the ways small-scale production can be advantageous, and disagree with my belief at how influential those factors are on the market, we're close enough to being on the same page for my own contentment.
If you disagree with the reasoning however, I'd prefer to keep discussing it until I learn of any major flaws in what I believe.