The indecisive client
This client has final approval on all intermediate phases of projects. It is only when projects are approaching the finish line that the "higher-ups" get involved, and in more cases than not, this results in additional feedback and more rounds of revisions. Getting approval from all decision makers is an integral part of any client partnership; however, when valuable input is withheld until the tail end of projects, completing a project on time becomes a difficult task.

What agencies can do: Agencies can help keep last-minute revisions to a minimum by cultivating relationships with contacts at all levels of their clients' organizations. This way, if and when problems surface, an existing working partnership is already in place so a plan can be developed collectively. Please note: This isn't to suggest that agencies should go over the heads of the people with whom they work on a regular basis. But by understanding the internal infrastructures of clients' companies, agencies can at least be a part of the approval process.

On a side note, this client is why weekly status meetings were created. But it works in an agency's favor to document pending approvals and delays so everyone knows the new project timeline.

The tester
Testing is never a detriment to a campaign. It enables agencies to make appropriate adjustments and get the most out of every aspect of a campaign. But challenges occur when client budgets do not afford agencies the leeway to test everything the clients want. Testing is not free, and media fees are likely unavoidable.

What agencies can do: To accommodate this client, agencies should focus on only a few offerings and be cautious not to spread budgets too thin. Constant testing of multiple campaign facets will likely never generate the return this client is anticipating. For agencies, it is best to work these pain points out earlier rather than later.