What are the benefits of variance analysis? How can such analysis be detrimental rather than beneficial to the organization?

Headquarters are contemplating charging each store a 5% marketing expense based on sales. How will that affect the operating profit of the store and the money available for managerial bonuses based on actual results for the past year?
Write a 4- or 5-paragraph memo to the division manager explaining the flexible budget variances; how to interpret the information and what action, if any to take. Comment on the 5% marketing proposal too. Start with an introduction and end with a recommendation. Each of the four or five paragraphs should have a heading.
Start with an introduction and end with a summary or conclusion. Use headings.
Discuss how to interpret static and flexible budget variances.
What are the benefits of variance analysis? How can such analysis be detrimental rather than beneficial to the organization?