When touching base with his vast network of NBA confidants, Kerr has been largely unwilling to grumble over his private suffering, but those who know him well constantly ask the Warriors' staff: How bad is it? The discomfort has never truly left Kerr in the past two years, but the symptoms did become grudgingly tolerable – until now. Kerr will forever regret undergoing that failed back surgery in 2015, regret it for the toll the spinal fluid leakage has caused him with ongoing headaches and nausea.