When you look for a mortgage loan you typically end up working with a loan officer.

This is true of the loan officer you meet in your neighborhood bank, a mortgage broker, or a dedicated representative of an online lender.

There needs to be someone who can track and organize the paperwork and status of the refinance process.

There can be lots of different paperwork that is involved in a mortgage loan, including but not limited to:

income
assets
work history, job verification
2 years of W2s
a month of pay stubs (for biweekly checks make sure you cover all 30 days!)
3 months of banks statements
Business bank statements
Company tax return
CPA letter certifying that you filed as a self-employed person
This person can function as a resource to you up front to help you decide what kind of loan you are looking for:

fixed or variable
loan length (15 years, 30 years, 40 years)
size of down payment
advantages and disadvantages of a prepayment penalty
paying points or financing closing costs
Make you you understand what your loan options are upfront. The loan officer should be able to answer these questions for you, gather your loan application and supporting documentation, and work with third parties (escrow, underwriter, appraiser, etc.) to get your loan done.

Because the mortgage process can be so complicated it makes sense to be available to your loan officer during the whole process. Timely responses to their questions can help you get the mortgage done faster.