Unfortunately, this seems to be quite a common occurrence for this and other similar products. If you see “Water, Stearic Acid, Myristic Acid, Potassium Hydroxide, Coconut Acid, Glycerin, Fragrance, Triethanolamine, Sodium Hydroxide” on the label, like so many products out there, it is a soap based product and soap based products dry out with time. They do contain "glycerin" which is a humectant and draws water into a product sometimes that is not enough to keep the product in its original state. Sealing the lid tightly after each use is essential to help to keep a soap based shaving cream from drying out and using it frequently will also help rather than leaving it for months and months without usage.
Production techniques are also important and I have photographs of workmen stirring and stirring large vats of shaving creams. It may be that they are looking for a certain consistency or processing the batch for a certain length of time but it they don't weigh the batch, determine the water evaporation percentage and replace it then the batches could have an inconsistency in water percentages from batch to batch that could result in a product that has too much water in it or too little! My batch size is small enough that I can weigh the batches during production to make sure that the water percent that I start with is the same when I finish the batch! I now start with a higher percentage than needed and process the batch, weighing it until it has the right consistency and has the correct percentage of water in it. The only other variable in this production can be the fragrance which may affect the consistency of the product but generally if your formula is a good one and you make sure it contains the correct amount of water from beginning to end then you should get a consistent product!