SGA says he doesn't want to keep playing in his 40s and will retire once he loses his rhythm:

I absolutely believe I can ...... but I won't ...... I don't want to miss that much of my kid's life ...... And there's always a certain point in your career where you peak. I don't blame the players who are still playing. They love the sport. But I think the ultimate goal of my playing is to see where I can be at my best. Once I find the answer and it starts to go downhill, I think, well, what am I still playing for? Once I find the answer, I'll get on the first boat out.