In outsourcing the organisation saves hiring cost of staff, training and knowledge transfer. In addition, it could save cost by limiting outsourcing to a period. The major time savor will be the cost of learning as the resources deployed through outsourcing will be well qualified to undertake the job within a small period.
Specialized resources are very scarce and costly, It is almost impossible for any organization to retain all the skills that are required to manage their systems. As in house resources are not only subject to normal staff turnover but they are constantly required to be trained and updated. Further, as specialized skills are required for relatively shorter duration (only to optimize/ stabilize the system), it is not a wise decision to keep them as part of the permanent work force.
Outsourcing of these specialized jobs not only provide stable support but one can get relatively better resources to carry out a specific job.
To have a stable and effective system support at all time the organization, requires an excellent knowledge management, where the persons handling the job are well equipped with the knowledge that requires to carry out the job. In case of in house staff, it has some limitations. As in case of some specialized task , the organization relies only on a single resource because one can not keep several redundant resources for every task at all times.
The best way to get out of this situation is to outsource that job to specialist organization.