How do you control who is allowed to create forms and workflows? Do you allow all site owners to do their own or do you have a group that creates them for the entire organization?
I've seen both as a consultant. Site Owners in some places, or a defined group of designers in others. The decision comes down to Governance.
Though it is easy to begin creating workflows in Nintex for anyone, there are a few things to consider when designing. Use of History data, number of workflow running at once, database use, and many others. It can come down to many small decisions too. Such as, how many workflows to you envision will be created? If you think 50, or some imaginary number of significance, you may want to consider the side effects (like lists with 200,000 items because no management is considered for history data, or there was an endless loop).
Its different for different organizations. Ours is based on our governance document. You just don't want any user to have this capability. If they do something wrong, they can crash the servers.
Ingo Ehlers I will try to post a governance blog or start a community conversation about it later this month. I think it is an important topic and is sometimes overlooked. But if I can forward to you a link to get a better understanding of some of the architecture, please review Defensive Workflow Design Part 1 - Workflow History Lists and the related links. Especially part three of the series. It's no all about governance, but it is related.