How do instructors select a distance learning modality?

Selecting the approach should not done lightly as it holds the key to success or failure. Often those with access to certain technology force it upon the instruction without thought. There is a danger in this not only to the instructor but, more importantly, to the learner that might walk away from a class frustrated and with a negative view of technology mediated learning that might affect him for years to come.

The key is to always perform an analysis of the needs of the learner, the instruction, and the proposed medium for delivery. The question to ask is whether these three are in alignment, and whether the technology appropriately supports the learning objectives.

Rather that be repetitive here, I suggest you visit the ADDIE section of this site where information is provided in course design and matching technology to instructional needs.