The last time he wanted to sell was when the fans turned on him one or two years into his ownership. He couldn't recover his investment with any of the offers, especially after we got relegated. Then we got good crowds at a lower league, came back on the first attempt, sold a player for 35m, and the PL got a lucrative tv deal. He realised all that and that he wields all the power with fans helpless against him. We're getting some profits in, he's not losing money (even harder to do so with the increased tv revenue), gets free advertising in SJP and on screens worldwide and barring a catastrophic relegation to league 1 he won't suffer a loss on his investment.
We missed the window where he was desperate to sell up. Doubt Ashley will ever do so now unless an Arab with oil money comes in.