Evaluating vendors is a tricky proposition. Even if your technical evaluation is perfect, your business evaluation can be wrong for the same reason that picking an individual stock is nearly impossible.

There are often pivot points in the company's history, both for the vendor you choose and the vendor you don't choose. For the vendor you choose, the following could happen in the next few years after choosing them:

* Product End of Life: Your chosen vendor could stop development unexpectedly.

* Acquisition: Your chosen vendor could get acquired and ignored.

* Dead Vendor: Your chosen vendor could shut down.

If you choose the "right vendor at the wrong time" it's not really your fault but it doesn't make your situation any less dire. In many of these cases you have a burning platform, it's more a matter of when, not if you move.

On the other side, there are often vendors you eliminate for valid reasons, but turn out to be the wrong ones 4 years later:

* Vendor Didn't Want You: A vendor enters a new market that previously they were not focusing on.

* Not Customizable Enough: A vendor starts allowing more flexibility in an area where previously that part of the system was closed to customization.

* Early Adopter Skittishness: A vendor had no reference accounts you felt comfortable with.

If you were making your decision 3 years later, you might see that vendor differently - but your timing did not match the vendor's timing. In this case, you are sometimes on a solution which may have been optimal for a time, but is now no longer optimal.

If you were to make the same decision again, you would make a different one. These are difficult decisions because they are expensive and complex. No one replatforms every 3 years, and perhaps the vendor you are on is not dead, it's just not ideal.

In this case, the solution is often not a big bang - it's more about your roadmap and sequencing. There is not a single approach that works for every company, but safe to say the decision is based on a combination of:

* Board and Investor priorities

* Financial priorities

* Technology priorities

* Brand and Customer priorities

* A clear picture of your end state.

One of my favorite phrases from Lewis Caroll in Alice in Wonderland also applies to eCommerce: "If you don't know where you're going, any road will take you there."