Suppose a table tennis player goes to serve. They throw the ball but for whatever reason decide not to play it. Instead they catch it with their hand.
Is this a service fault and therefore a point for the receiver or a let?
Throw up and catch - Table Tennis Rules
Q: If I toss the ball up but I don't serve and catch the ball back, Is it a fault serve?
A: Yes that is your opponent's point. As soon as you throw the ball up it is in play. - Alois Rosario
Ref: https://www.pingskills.com/table-tennis-forum/throw-up-and-catch