Time for cataract surgery depends on many factors including your quality of life, your occupational needs, personal health, grading of cataract, associated complications (if any), etc. With treatment, chances are good that you will recover quickly and experience a much better quality of life. Patients with cataract should ask their doctors about it sooner rather than later. If your eye doctor recommends that you wait, ask him his reasons for suggesting this. He may have a legitimate concern about your health that you need to address.
Your doctor can help you decide the best time to have surgery if you develop cataracts. For some people, despite their age, cataracts remain a minor problem. If cataracts do impair the quality of your life you need to address the problem.