There are two possible pathways here, you can work with the company to try and improve your performance, change perceptions about your performance, and stay with the company. Alternatively, you may decide that the environment or circumstances will make it difficult to achieve the plan, and the writing is on the wall already. In that case, you may decide to leave the company and find suitable alternative employment. Remember it’s not the end of the world if you are placed on a plan, but you need to be realistic about why this has happened, and be clear about the steps that you need to take to successfully address the company’s concerns about your individual performance.