Controls are put in place to prevent a process from proceeding further if there are errors or if something goes wrong. For example, an ecommerce website would have a control point of credit card validation. If the ecommerce site did not verify the credit card was valid and the charge was able to go thru, then the company would have to cancel all orders that are processed without payment being successful. Another control point would be live inventory updates and checks. This would prevent a customer from purchasing something that was not in stock. Control points helps the process maintain quality.
Provide an example of control points in your daily lives that you can observe.