Overall, yoga cultivates a positive outlook, a strong and healthy physical body, an ability to handle difficult and stressful times with balance and clarity, and a sense of inner peace. Many of the breathing practices help to develop mental strength and increase memory which of course is great for students. Additionally, the practice of asana, pranayama and meditation help to dissolve strong emotional states such as depression or anxiety. Yoga is considered a mystical science and it has been evolving for thousands of years. I think it has lasted because it is so clearly effective.
People tend to feel the benefit even with a very short daily practice of ten minutes a day.
I think that the instructor makes all the difference in the world. Many people have tried yoga and have stopped because they didn t feel good in the class. There are many styles and interpretations of the practice of yoga. I always advise people to find a teacher who works for them. Patience is important for the beginning student as well.