What was the critical functional flaw associated with Milton Reynolds' highly popular but short-lived 'Reynolds Rocket'?

Answer

It relied on gravity feed, leading to poor consistency and widespread leaking

Despite its initial success as a marvel of engineering sold at a luxury price, the Reynolds Rocket suffered because it used the unreliable gravity-feed system, causing consumers to lose interest when it failed functionally.

What was the critical functional flaw associated with Milton Reynolds' highly popular but short-lived 'Reynolds Rocket'?
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