This article is about the musical term "solo"; for other uses, see solo.
In music, solo means to play alone. This does not necessarily mean that no one else is playing at that time, only that the soloist's part is the most prominent. In jazz it is common for each player to improvise a solo in turn, while others continue to play but more quietly.
A related term is soli, which means that a whole section of a musical ensemble is playing the same thing at the same time.
In some context these are interchangeable, but 'soli' tends to be restricted to classical music, and tends to refer to either the solo performers or the solo passages in a single piece: it would not often be used to refer to several pieces that happen to be for single performers.
Although there may be passages where only the soloist is playing, generally the solo part is accompanied by the orchestra: its distinctiveness and prominence are what makes it a solo.
There are pieces for solo singers, possibly accompanied; there are pieces for soloist and chorus (like concertos, but that word is not usually used); and there are solo passages in choral works.
This does not mean that a Soloist who accepts a draw, or who survives or is eliminated when someone else wins did not accomplish anything, nor does it mean that he or she did not play well.
The Soloist accepts the fact that he or she did the best that they could do, and failed, and will accept failure with grace, knowing that each failure is a learning experience that will aid in achieving success in the future, but the Soloist never thinks of anything less than a solo as a success.
Soloists do play in tournaments, for social reasons, to help promote a Diplomacy forum that may be sponsoring the tournament, and if the tournament is open to all, to play against opponents they might never otherwise encounter.