Why is measuring the depth of the footing from the side considered inaccurate for grade checks?

Measuring the depth of the footing from the side is considered inaccurate for grade checks primarily because it does not provide any information on elevations. When performing grade checks, it is essential to have precise elevation measurements to ensure that the structure is built correctly according to the specified plans and designs. Side measurements can fail to account for variations in terrain or soil and may not reflect the actual depth needed for accurate placement of footings relative to the grade line. Accurate elevation data is critical for achieving proper drainage and structural integrity, which is why relying solely on side measurements would not yield reliable information about the footings' depth in relation to the overall construction plan.