Roots are a bigger problem for underground drains than people realize. They can get through the smallest cracks and gaps and grow in them and expand them.
My dad installs underground drainage and sometimes his team have to fix them and clean them too. He has had to fix so many drains that were completely clogged by roots growing in them.
If the drains are made of good materials and installed correctly, this isn't a problem. That's why people need to work with professional companies that have a lot of experience with drainage.