A good team member plays to his strengths, but a wide breadth of ability is still valuable. It means you can understand what your teammates are doing. It's not

A good team member plays to his strengths, but a wide breadth of ability is still valuable. It means you can understand what your teammates are doing. It's not requisite and sometimes is unreasonable to expect in multi-domain projects, but that doesn't mean it isn't valuable. Similar to philosophies on management. A good manager does little hands-on work himself, but he will generally make for a better manager if he could hypothetically fill the shoes of each of his reports. Not that he should ever actually do that, but it means he understands what they are doing.