You might want to work with an outside expert if any of the following scenarios apply to you:
You don’t have any inside SEO resources, are not in a position to hire them, and need someone to work directly with your development and marketing teams to get your SEO campaign going.
You don’t have any inside SEO resources, and while you want to build a team, you need to jumpstart the process in the meantime. You may also want to use your outsourced SEO practitioner to help train your team.
You have an inside team but it is missing a key piece of expertise, or you just want to sanity-check the conclusions your team is drawing or see whether they are missing anything. In addition, since SEO at its best involves lots of brainstorming, an injection of fresh ideas can be just what the doctor ordered.
You have an inside team but they are busy working on other projects.
Regardless of the scenario, an outsourced SEO professional can bring two assets to the table that will be difficult for your internal team to provide:
If you hire an industry-acknowledged expert, that person can often speak with a voice of authority that is not readily available to the inside team. This is not necessarily because the inside team are less senior; it’s just because they are, well, inside. Familiarity may not be breeding contempt in this case, but it can still make someone seem less of an expert, perhaps because that person’s occasional mistakes ...