In most cases it's preferable to keep your natural teeth for as long as possible rather than having them taken out. However sometimes teeth are so badly damaged or broken down that tooth extraction becomes the most viable option.
When a tooth is damaged to a point where reconstructive work would not be sustainable, extraction may be the most logical option. If there isn’t enough space in your jaw for your wisdom teeth to come through, they may become impacted (stuck behind the tooth in front) and need to be removed. Teeth may also need to be extracted due to infection.