Majid is an expert supervisor in a garment knitting factory having an experience of 20 years. He is supervising a knitting line at the moment having 5 machines. The knitting line is experiencing a situation of low output. Majid goes for a line inspection in order to identify the performance of the machines. The process of knitting is completed with a worker at the end of line stitching a zip on the garment. Majid has experienced that the machines are working to their full potential. But he is still worried about the low output. The other knitting lines have also 5 machines but the output is up to the mark. Requirement: Using the "Theory of Constraints", in your opinion what could be the constraint in the given situation.

How it can be removed in order to increase production keeping the number of machines?