I don’t know why people are assuming we can create a vaccine. There’s no vaccine for any other corona virus.

Due to lack of need. Creating vaccines for the common human strains of corrona virus would be spending a lot of effort to stop the common cold (possibly including a flu like seaaonal vaccine).

Work on SARS resulted in cadidate vaccines, but was abonded before human trials because of succsefull containment.

Work on MERS resulted in a vaccine that is currently showing succsess in humans.

Work on SARS-COVID-2 is starting from those, and already has canditate vaccines based on modifying ones we know showed signs of success against other corona virus.

Maybe this will turn out to be another HIV, where a virus proves ellusive, but I haven't seen anything to suggest that.

Because we're already starting trials of one: https://time.com/5790545/first-covid-19-vaccine/

There's a bit of a description there about why this approach is different.

Obviously we’re trying, but I wouldn’t assume it’s going to be successful. It’s most likely that it won’t be.

Human coronaviruses are usually just common cold, so there was no need to make them before.

Maybe we should try having more common colds... In wonder if that would help to create resistance.

That's a hypothesis why young children aren't affected by COVID-19, maybe they had more exposure to related viruses due to school. Currently, no reported death for children; but mortality rate is significantly higher for 50+.

There was once a vaccine for the common cold. However it only covered a couple of the 300+ different common colds and so it made no statistical difference.

Realistically, creating a vaccine will take in the order of years.