Consistent return value

[drselump14]

I'm sorry if it's already been discussed. I can't find it in the issues.
I was wondering if there is a specific reason for keeping value | { :error, term } format for several functions and using {:ok, value} | {:error, term } for other functions.
Isn't it better to use the latter format consistently?
The former format not working well with with keyword, so I prefer the latter format.

Any help would be appreciated