something impossible to do with synchronous online or face-to-face interaction

Timezones and cultures: If you have a geographically dispersed set of learners, any synchronous events will introduce timezone bias; additionally people may have variant weekend days, national holidays, and other important days they cannot meet Families and busy people: If you teach mostly non-traditional students who have either jobs or families, their time may not be as flexible and they may struggle to commit to synchronous meetings. Recording meetings for them to watch later could work BUT they would have FOMO (Fear of Missing Out) and you would lose their active participation in those meetings Technical: If some of your learners have infrastructure issues (e.g., live in remote/rural areas or developing countries where bandwidth is low or unreliable) then audiovisuals will discriminate against them, more so if this is live audiovisual interaction. Even those with relatively stable infrastructure occasionally struggle with connectivity and/or with mic/headset working properly every single time they connect Language: If some learners are not native speakers of, or not fluent in, the language of instruction, then they may prefer the additional time needed to interpret and reflect before responding

affordances and limitations of each modality