When receiving a fabric in the workroom WE ALWAYS CHECK the pattern repeat, by measuring it on the actual fabric. Quite often there can be a slight variation to the figure quoted by the supplier in the fabric details. This difference is usually not enough to require more fabric, but can change the calculated adjusted cut drops a bit.
Sometimes though the fabric supplier gets it plain wrong and here is a recent example.
With the fabric in the image, the supplier gave the vertical pattern repeat as distance A in the diagram. At first glance this looks right, but when you look closer you will see the pattern is not consistent. Look at the areas marked by the red circles and you will see the pattern repeat is actually distance B (three times that quoted by the supplier).
If we had cut and measured according to distance A, the joins would have looked really bad.