I did not find Jane to carry a positive tone in any of the forms: email, voicemail, or face-to-face. As I viewed each of the modalities I interpreted a similar meaning. In the email I got the message of, if you can't do it, then I will do it myself. In the voicemail her tone came off as somewhat condescending, as did her tone in the face-to-face meeting; however in the face-to-face meeting there was the addition of non-verbal communication that sent the additional message that Jane was not happy, even though she showed a big-fake smile at the end. In each of the modalities I noticed right away the use of "I", "your", and "my own." There was no indication of teamwork. One difference I noticed was in the email the message seemed authoritative, while in the voicemail and face-to-face to meeting Jane seemed somewhat passive.
I think the same message could have been conveyed in a more positive manner. I understand what as a project manager it is Jane's responsibility to make her team accountable and to create a sense of urgency, but there are proper ways to approach the situation. "Merely assigning people to perform selected tasks on a project does not create a project team" (Portney, etal., p. 301). Good communication throughout a project will help to create a team atmosphere.
References
Portny, S. E., Mantel, S. J., Meredith, J. R., Shafer, S. M., Sutton, M. M., & Kramer, B. E. (2008). Project management: Planning, scheduling, and controlling projects. Hoboken, NJ: John Wiley & Sons, Inc.
The Art of Effective Communication [Multimedia Program]
http://mym.cdn.laureate-media.com/2dett4d/Walden/EDUC/6145/03/mm/aoc/index.html