Failed to get "the prospective demand of the undertaking"

The expected future demand for the enterprise being undertaken.

Thanks

The inquiry was exceptionally thorough and painstaking because of the scope and the prospective demand of the undertaking for large resources of wisdom and tact, professional skill, energy, time, and funds.

More (unfortunately lacking) context: The proposed "undertaking" was a research study that Dr Andrew Kinsey wished to make of human female sexuality. Kinsey applied for funding (which was granted) to a committee set up by the US National Research Council. When the result of the research, the celebrated work "Sexual Behaviour In The Human Female" was published, it included a preface written by members of that committee. It is a portion of that which oristarA has quoted above.

Before granting financial support for the study, the committee made an "inquiry" into Dr Kinsey's standing as a scientific investigator, and "his plans, program and method". The enquiry needed to be thorough because the "undertaking" (the study) was likely to demand the things listed: wisdom, tact, skill, energy, time and funds.

SExcellent!