(This is my understanding) You need to specify node assignment criteria in 2 places:
- Configuration Advanced Setting
- Step Setting

Criteria are inherited and joined through the configuration hierarchy and the step hierarchy. This means that you cannot override the criteria on a step to use a particular node if that node has been excluded at a configuration level.

Suggestions:
- On any UI where you can specify criteria, display all currently applicable criteria and where they are inherited from.
- Allow overriding and 'nullifying' of criteria, i.e. 'Do not use this criteria which has been inherited'
- If a build fails due to 'node cannot be found which matches criteria', log all of the criteria and where they are specified so that this can be debugged.