Getting an accredited (#1) Coach and, continued learning (#2) are very critical.
Reputation (#3), track-record, coaching outcomes, coaching experiences (#4) are very important to sustaining any coaching relationship.
Can an internal coach, who I presume is part of the organisation, be really effective?
Will each coach not bring his/her own creative inputs into the art & process of coaching?
A transparent process may hamper the coach.
Surely, the defined outcome will enable ROI of the initiative.
The larger question is : Is internal coaching better than external coaching ? Or is it subjective ? Can the internal coach be neutral and have a zoom-out vision of an external coach. Also not bogged down by corporate culture and practices ?