When applying a Prepare recipe to a dataset, Dataiku will often reinterpret storage types and meanings. Note that I am not referring to Dataiku guessing the storage type or meaning for a derived column created within the Prepare recipe. I am referring to existing columns, which were often previously configured with the correct storage type and meaning, being changed.
This has caused hours of frustration, rework, troubleshooting, and extra processing across our teams. Not all users are aware of this behavior or remember it in the moment, causing them to hunt down an issue that Dataiku created for them. For those that are aware of this behavior, it is incredibly frustrating to configure your dataset correctly at the start of a project and have to re-check columns at various points to ensure Dataiku hasn't second guessed your choices.
I believe there should be an environment and project level setting to disable this behavior. If that is not a viable option, there should minimally be the ability to "lock" a storage type and meaning so that Dataiku will leave it as it has been set. Implementing all three would obviously give the most flexibility, but my preference would be a simple switch at the environment and project levels. While I'm mentioning the Prepare recipe here, I remember seeing documentation (which I cannot find now) stating that at least one other recipe has the same behavior. The implemented fix should work regardless of the recipe.