The requester checks your responses and rates your skill in performing this type of task. Skills are rated on a scale of 0 to 100 points. You can view your skill level in the section.
Skill levels allow the requester to offer tasks to users who do a good job. The more skills you have and the higher your skill levels, the more tasks you will have to choose from.
If you don't do well on a certain type of task, you receive a low skill level. Over time, you might lose access to these types of tasks.