what is one reason that the Constitutional Convection decided they needed a document to replace the articles of confederation?

They needed  a new central government which would be essential for the development of power and potential of the United States.

Explanation:

The constitutional convection was held in Philadelphia from May 25 to September 17, 1787. It consisted of 55 delegates from 12 states.

It was held to assume the primary task of replacement of amendment of the article of confederation.

The article of confederation provided the framework for governance since the declaration of the American revolution from Britain.

Under the article of confederation the federal government lacked the power to exert taxation, had could not to regulate commerce and was unable to resolve conflicts arising between states and a central government which was able to do this was required.

So, one reason why the constitutional convection decided they needed a new document to replace the articles of confederation was that they needed  a new central government which would be essential for the development of power and potential of the United States.

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