As stated above, CROs should be used when necessary. If a company has the time and money for it, then a reputable CRO would not be an issue if it was utilised. In addition, some small companies could possibly benefit from the use of a CRO, especially if they’re new in the game and do not have the resources to run clinical trials themselves.
However, if a company is large enough and based well, moving clinical trials in house would be time and money saving in the long run.