How many teams are desperate for a guy like Smart?
Spurs, Hawks, Grizzlies ... there is a nice list. While the Celts have an eye to make the finals, these teams would want nothing more than to make the playoffs and get past the 1st round. Smart is the type of player/character that can help
Instead of overpaying for an ok talent like Otto Porter 20 plus million. Its probably a safer investment to pay Smart 15 million for 3 years (maybe even 4 if it comes down to it).
I just can't see Danny/Wyc paying this to a "glue" guy when you have to worry about paying Kyrie, Brown (likely near max), Tatum (max) sooner than later .... plus need to worry about bringing back important pieces like Baynes etc
This is why Horford and his salary is tough is to swallow. It means if affects to resign secondary/semi starting pieces like Smart, Rozier.
At the end of the day
Celtics: We will give 75 percent of what the market can. Can you stay? you are an important piece
Smart/Rozier: So while you guys are generous to pay/overpay Horford etc. (and I think I'm just as important) I have to take a paycut? ... thanks for everything, but I'm leaving. Might be one of my last chance to obtain top dollars in my career.