You might think that making the casual snapshot or candid photograph might not lead you to become a better photographer. You thought wrong. Practice is practice and even the process of making candid frame photographs can help develop your eye for lighting, composition and much more. Here are a few ways that candid photography can help your development as a photographer.
Observing and seeing on a regular basis
Considering the background as well as the subject.
Being aware of the quality and direction of light
Understanding how ISO affects your shutter speed
Notice how color changes depending on the light source
Learning how to adeptly photograph a group of people
Discovering how to effectively photograph under low light
Becoming sensitive to white balance and color accuracy
Making unusual perspective choices
Learning to use flash both as a fill and primary light source
Great opportunity to get familiar with your camera and lens
Developing your personal approach to working with people
Accumulating a number of portraits
Understanding the high ISO limits of your camera