What is the main purpose of supervision?

Person in the first-line management who monitors and regulates employees in their performance of assigned or delegated taskswith safety rule.

According to manpower make the daily plan.

Follow safety rules.

Report Handling.

Motivate the staff.

Maintains inventory and supplies by receiving, storing, and delivering items; securing warehouse; supervising staff.

As a Public Relations graduate, my understanding of supervision goes like this: it is the act of ensuring that important projects and strategies are performed by the employees on the right track all the way through small objectives. In addition, if the organization strives to stand itself out among other companies or even its competitors, supervision must focus on maintaining strong relationships between the employees when conflicts clash between their tasks and strategies. Otherwise, the reputation of the organization will gradually deteriorate and publics won't rely on its services and facilities. Crisis management, problem solving and critical thinking are the key elements that supervision should focus to keep the company operating systematically until the final goal is achieved. Even when arranging meetings with other clients or representatives from other companies, supervision keeps an attentive eye on its performance when collaborating together to produce a new idea, or sell a product to the publics everywhere.

I could be wrong about some parts I explained about supervision. If there any doubts or questions, you are welcome. Cheers! 

Supervision is getting the thing done correctly within the schedule time by motivating the workers with frequent visit to the site or workplace.