Users will be able to complete the online form more easily if it is shorter. Cutting away needless inquiries that aren't directly relevant to the work at hand or that can be answered with a simple "yes" or "no" is one of the most efficient methods to doing this.
Use your best judgment since just because you have an extra field doesn't imply it needs to be filled in.
For example, if a user must supply personal information before entering their name and email address in order for your organization to fulfill their request, it may not be appropriate to ask for their opinion on on-site design development first.
That way, they'll be able to understand how crucial it is to enter these facts while completing the form.