Why hold back on telework?

As the Pete Seeger song goes, "When will they ever learn, when will they ev-er learn?" I can't help thinking about that song when I think about the latest telework survey that focused on managerial reluctivitus (my term for reluctance to approve telework).

The survey found that many managers continue to be uncomfortable with the idea of telework. They feel face-to-face contact is necessary to assure that the job gets done. Yet managers who already have employees teleworking find that productivity does not suffer.

There must be other, better reasons for holding back on telework approvals. Continuity of operations, pandemic flu and many other reasons give weight to the argument that telework's time has come. I'd like to hear some of the reasons why telework should not be done. I'd also like to hear from those who have made a successful business case for telework to their managers. What helped you to make the case?