The real question in why would White even want an extension in SA? He was drafted as a combo guard, who most thought wasn't really a PG, to Pop playing him almost exclusively as a PG. Spurs just made big investment in a PG, who hasn't demonstrated as much success as you have & has been every bit as inconsistent.
If you are White the only incentive to sign would be money, but we are talking about being OK extending White for the right price. I think there are alot of teams willing to pay him at least that "right" price while also giving him consistent 25+ minutes a game. If you are White, watching Forbes & at times Mills & Beli getting more minutes, I just can't see him being eager to do extension.
Add in that with no DDR last night, Walker gets almost all those minutes & White saw no increase. I can't see White or his agents thinking the Spurs are the best franchise for his basketball future.