Pros
You will learn about yourself, your strengths & weaknesses If you are receptive to criticism, you may grow as a person, in many ways, not just work-related Very bright, challenging people An upbeat atmosphere Promotes honesty, openness Free daily meals & snacks Looks good on resume
Cons
Principles, diagnoses, and drill downs are not applied thoroughly or consistently. Drill downs, or issue investigations, are you against the world. People with strong logic and debate skills usually prevail, regardless of the "truth". The more tenured employees generally prevail, regardless of whether they are "right" or not, because others do not openly challenge them. Progress on projects is frequently sacrificed in the name of excellence, resulting in severely missed deliverables and dates. Sometimes projects are stopped or scrapped altogether. "Trading floor" and basic infrastructure is so far below basic levels that it is perilously close to disaster. Company has not been able to make the evolution from a small startup to a stable corporate model because of its' resistance to outsider influence. The people who have been there so long "don't know what good looks like". Seasoned, accomplished people who come in are systematically dismantled until they are no longer believable. E.g., there are no integrated financial / procurement systems, poor annual financial planning (budget), HR department in disarray, IT org. has too many people and is largely ineffective.