There are several factors which make mediation attractive.  The first is COST.  Bringing a case to trial in court is expensive. Experts, witnesses, days in court = days away from work.  Mediation can be very cost-effective.

Second is TIME. Cases can take years to get in front of a jury.  Mediation can and is scheduled quickly and conveniently.
Third is RISK. Mediation is low risk. If the case settles, it’s over.  If it doesn’t, all your rights to go to court are intact.

Perhaps the greatest factor is CONTROL. In mediation, the case only resolves if the parties accede to the resolution.  The parties control the outcome. In a jury trial, assembled strangers decide the outcome, and the parties have little control, if any, over how things turn out.