Implement
The final stage of the process is also the longest, but that is by design. Leading up to this phase the emphasis has been on rapid 'throw-aways'.
Most clients despise the term 'throw-away' because they feel that you're throwing away time, which in turn is costing them money. I use the term here intentionally to refute this misbelief. The designer does throw away the tangible assets of the early process, but the important part of that work was in the knowledge and experience developed which saves development time in the long run.
Conceptualizing and prototyping are long term investments. They cost a little bit more up front, but they're worth their weight in gold in the long run. I think a good analogy to this is building a home. A lot of time goes into laying out the plans and making sure all the proper building codes are met. Can you imagine telling a builder you want a two story house, and he immediately began pouring the foundation? Or worse yet he finished the house, only to find that it didn't meet code and had to immediately be remodeled or even started over? Well, the same is true when you're designing or developing most anything else.
The implementation phase is hopefully the most uneventful phase of the entire process, though this is rarely the case. Even the best planning can't account for every possibility, and you would have to be pretty arrogant to say it could. The reason for using a thoroughly documented process such as this isn't to avoid problems all together, but to minimize them as best as possible and certainly not to invite them into your project.
