For a sub-contract manufacturer, winning work normally involves establishing your company as a selected supplier, answering RFQs and then completing manufacture. For the end client , even where a supplier has been long established it can often be seen as a worthwhile activity to obtain competition quotes for constant re-evaluation.
As such a sub-contract manufacturer will often need to access multiple RFQ websites, have hundreds of components that all need to be quoted for, all of which will need to be chased up and evaluated for future quotes.