One of the greatest issues of project-driven organizations is the delay in their completion. Delay which has a nature of deviation basis and sometimes look so normal. Delay which instead of playing the role of a caution to managers, acts as a repetitive action. In such a situation the managers prefer to use the control tools and management of projects so that they can take a step for betterment. From these kinds of graphs we can mention Bullet Graph, Bar Graph, Pie Graph and S-Curve. Among these tools, S-Curve can be mentioned as one the essential ones. In this article, first we are going to define this curve; analysing its different usages, we will start with evaluating the role of this curve in management of deviation in the project and identify the problems and issues related to the usage of this curve in the second place. Finally, we will consider solving this problem, develop the S-Curve and introduce a new curve with the title of OS-Curve and apply it in two different projects and present its conclusions.