After Kramnik's recent announcement, Nakamura also said in a chess.com interview that he will retire from chess at age 40.
I am curious why a super GM feels the need to "officially retire" from chess (or a format of chess). Why not just stop playing but keep the door open for future events? Who knows, maybe you'll feel different after a break.
To be clear, I am not asking for speculations specific to Kramnik or Naka's mindset. I want to know what concrete, practical reasons there may be for a top GM to announce retirement, like sponsorship or contractual reasons as an example.
Update based on comments and whoever voted to close: I'm specifically not asking for guesses or opinions, but for insight from someone who have knowledge of a super GM's unique situation (be it legal, social, practical or otherwise) to elaborate why it is beneficial to announce retirement rather than simply stop playing.