The time will come when those holding major paintings will become reluctant to entrust them to the auction Russian roulette game and when top-notch dealers will take over as quiet arbitrators to channel the few masterpieces left in liberty toward plausible buyers. On a lower quality level, the process will be different, but the end result identical. Prices will also be pulled up mechanically, as a result of growing rarity and, accordingly, of vendors' soaring expectations. At some point, buyers will increasingly stall as they feel that they are no longer getting their money's worth. When that psychological stage is reached, the market for Impressionists and Modern Art will rapidly slip away from the auction scene at that lower level as well.
Auctions require quantity to make sense.
If the pictures are too scanty and the players willing to join in are too few, the auction system becomes irrelevant. Not least, its sophisticated structure and its high cost become disproportionate to the goods it handles. The end of the auction processing of Impressionists and Modern Art and, some time later, of Old Masters, as it stands now, is no longer inconceivable. I would not give it more than another two decades at the outside.