Principle: Root cause of every success needs to be analysed. The deliverable is discovered capability.
Each success is an event of capability deployment: something gets delivered: a closed deal, or prototype, or product, or a feature. Businesses are justified by outcomes. Therefore they naturally are focused on success and concerned about failures.
Better organizations aggressively attack failures by finding root causes beyond just personalities (5Why is one of such methods).
However, the successes often are treated in a more self-gratifying manner: "Mary the architect came up with a bright solution, which helped to deliver great value for the customer. Thus, next time ask Mary, she will figure it out." It is not unfair to say that Mary is the capability. Just keep Mary happy and ask for her help next time.
There is nothing wrong about this approach, one just needs to decide upon its price tag: are there specific skills or knowledge that allowed Mary to come up with her idea? Maybe these skills are transferable? What happens if Mary leaves? Will Mary have time once there are more projects? Can other team members pick Mary's skills?
This all is concerned with the organization's capabilities. Eventually, the answer may be that, yes, only Mary can do it (because of her talents, or expensive learning curves, etc) - but it would be an explicit answer, which would contribute to a better structured understanding of capabilities available to the business. (Notice: this reasoning is not just about creativity, which, although often soft and subjective, also is possible - e.g. lateral thinking as capability).
It is worth tracking each achievement back to the capabilities that made it possible. For example, 5Why method works for such success analysis and capability discovery, although originally it was meant for defects and failures (perhaps it could be called 5How in this case):
Obviously, the analysis above shows only one branch of reasoning; there may be more than one. Pragmatic contributions to the organisation's capability could be scaling in various directions: