Market factor is an extrinsic force that decides the fate of a product in terms of demand or the price.
The market factor can be any of the following-
Government Regulation - eg. Set top box being made mandatory in metros,
Natural calamity - eg . Floods in Thailand led to a low production of hard disks , as a result the prices went up 2011-12.
Composition- Lifebouy was reported as a carboxylic soap in the 90’s , so it had to be scraped off and re introduced.
There can be many other factors which may qualify as market factors.