Oh, and it's the same old story

Ever since the world began

Everybody got the runs for glory

Nobody stop and scrutinize the plan

-- Paul Simon, "Learn How to Fall"

Plan your work, and work your plan

-- Unknown, 19th Century

If you want a user experience that delivers for your business, and you want to be able to monitor how well it's doing, you need to plan this work before you build anything.

This is not process for process's sake. This is about hitting a bull's-eye, rather than shooting in the dark. To do so, there's a rational order to follow. Usually it looks like this:

Know and articulate your business goals -- immediate and future.
Posit requirements for how an experience is going to help you achieve those goals.
Validate and refine your requirements by getting input from stakeholders and users.
Make sure what you're trying to accomplish is feasible, practical, and measurable.
Iterate a design and test it with users, then adjust the design based on their input. (Repeat this step if necessary.)
Flesh out the design and document it, so builders can build it and testers can test it.
Build it.
Test it.
Deploy it. (Throw a party!)
Make sure it's doing what you want it to do -- review the success metrics and results regularly.

That's the basic process. Many complexities -- audiences, global considerations, delivery vehicles, and more -- but that's basically it.

Keeping to the Plan

If there's one things that's essential to know about the process, it's this: At any point during the process, you should have a clear line of sight from your original business goals to whatever step you're on. As well as a clear line of sight between any step and any of its precursors.

Suppose you're in Step 3 and you're performing usability testing. Is this test relevant to what your business is trying to accomplish (Step 1)?

Or say the design is being fleshed out in wireframes (Step 6). Scrutinize them -- are all of the requirements stated in Step 2 accounted for? (When visual designers present to me, I hold them to a standard: I expect to recognize the requirements in the design. It is not the designer's job to drop requirements or make up new ones.)

The plan and the process keeps everyone on-message, on-target. So plan your work, work your plan, and keep scrutinizing the plan.