When is this a problem?
When any module includes more than 50 line items.
Why is this a problem?
It goes against the best practice, which is to not include more than 50 line items in a module.
How to correct:
Break up the module into separate modules, especially if any of the line items use subsidiary views.
Questions on this topic? See Are there more than 50 line items in a module? in our Model Optimization Checklist forum.