He stayed because to stay was easier than to make an immediate decision and act on it energetically.

He had very little will power to begin with and his mode of life had weakened his original endowment.
After the judgment had been given in favour of Queensberry, Oscar drove off in a brougham, accompanied by Alfred Douglas, to consult with his solicitor, Humphreys.

At the same time he gave Ross a cheque on his bank in St.James's Street.

At that moment he intended to fly.
Ross noticed that he was followed by a detective.

He drew about L200 from the bank and raced off to meet Oscar at the Cadogan Hotel, in Sloane Street, where Lord Alfred Douglas had been staying for the past four or five weeks.