Developers will understand the requirements better and will design and implement the software in a better way.
It will give the developer an understanding of how to write code better and how to identify potential issues before they become problems.
It improves their debugging skills, and they become more efficient at identifying and resolving issues in their code.
Developer gets a better knowledge of customer requirements to make the product defect free and according to customer demand.
Developers will discover what is advancing in testing, like automation, left shifting, etc., to make testing easy for them.
Continuous learning will improve their skills and help them accelerate their career.