Differentiate Mandatory Provision from a Directory Provision. What factors decide whether a provision is directory or mandatory?

Practically speaking, the distinction between a provision which is 'mandatory' and one which is 'directory' is that when it is mandatory, it must be strictly observed; when it is ‘directory' it would be sufficient that it is substantially complied with. However, we have to look to the substance and not merely the form, an enactment in mandatory form might substantially be directory and, conversely, a statute in directory form may in substance be mandatory. Hence, it is the substance that counts and must take precedence over mere form. If a provision gives a power coupled with a duty, it is mandatory: whether it is or is not so would depend on such consideration as: the nature of the thing empowered to be done,the object for which it is done, andthe person for whose benefit the power is to be exercised.