There might be hundreds of different uses for an online change request form. Depending on your industry and business, you might be willing to give your customers a quick way to request a change to the project being worked on.
For example, a change request form might be useful for printing or manufacturing. If you're working on a large batch of products, the orders for which are submitted well in advance, you might give your clients a quick way to request the changes to the particular order.
You might use a simple text field in Paperform to let them describe what changes are required. If you're receiving many such requests, you might also include a multiple-choice field to let your clients select what aspects of the project will be affected by the change. You might later synchronize your forms automatically with Google Sheets — which might save you lots of hassle in the long-run.