I think a coach does four things:

1. Mentoring - a coach should have the capacity to empathise, and to relate the coaching experience to his or her own mind-set, world view and direct experience of analogous situations and contexts.

2. Facilitation of learning - a coach should have the capacity to transfer knowledge, either tacitly or explicitly, in a way which is beneficial to the client.

3. Problem solving - a coach should be able to deploy a variety of problem-solving processes so that the client can methodically work through the parameters of a problem to evolve a solution which fits.

4. Offering critical friendship - a coach, by virtue of the trust and confidence s/he has developed with the client, should be able to question appropriately

Skilfull questioning is critical. It's not about answering questions, but asking them just in time and precisely.