To make that analogy more precise, the dozens of volunteer groups are each making a different tank, each with its own quirks, strengths, and weaknesses. All of the tanks being constructed can fire 7.62mm rounds, but their main cannon size varies... 70mm, 90mm, 105mm, and 120mm. The physical sizes of the tanks differ... some are Western tanks, while others are Russian. Some use a Vickers tread system, others use the Christie system. Additionally, learning to drive one tank fully does not grant you equal mastery over any other tank; the size, bulkiness, handling are similar, but the control mechanisms are completely different: some have a single joystick, some have steering wheels, some have dual steering shafts. Some drive-by-wire, others are more manual.
Additionally, aside from the fact that all these volunteer groups are working on a tank, there is little-to-no cooperation between them. Instead of collaborating and making one "supertank" that does everything anyone could ever want, they decided to specialize. Some tanks are fast, some have incredible passability, some are heavily armored... the list goes on.
So when someone comes to this intersection, if they happen to glance at the volunteer tank engineer corner, all the see or hear is dozens of different tanks, in various stages of readiness, and hundreds of bullhorn-abusing people, their amplified voices joined into one cacophony of accoustic mud.
So these people, who merely want something to drive around, look anywhere but the tank corner.
Granted, people coming for a tank will go get a tank. But if the volunteers want others to buy tanks as well, something needs to be done.
