Reference

Albert Myer faced significant difficulties in staffing signal personnel initially due to the use of a "detail system." This system required officers who were assigned to signal duty to maintain their association with their original units, which led to challenges in their availability and focus for signal corps tasks. Myer envisioned establishing a separate, trained professional military signal service. However, due to the constraints of the detail system, this vision couldn't be realized immediately, resulting in reliance on temporarily assigned personnel for nearly three years (source).

Here is an image of Albert Myer: