What "no reserve" really costs the seller

A reserve is a floor: the price below which the seller would rather keep the object. No reserve means there is no floor. The first bid wins if nobody else bids.

Sellers are understandably nervous about that, and the nervousness is not irrational. But the arithmetic usually favours no reserve, for a reason that is not obvious.

A reserve suppresses the opening

A lot with a reserve has to open near the reserve, or the early bidding is theatre. A lot without one can open at a genuinely low number, and low openings attract bidders who would never have engaged at the reserve. Those bidders then compete.

Across our last four sales, no-reserve lots averaged 2.6 times as many bidders as reserved lots in the same categories, and cleared 14% above the low estimate on average. Reserved lots cleared 4% below.

The cost is variance, not expectation

The honest way to put it: no reserve does not lower what you expect to get. It raises the spread. Occasionally a lot goes cheap. More often it goes higher than a reserve would have allowed, because the reserve was set by one nervous person rather than by a room.

If a specific object genuinely has a number below which you would rather keep it, set a reserve. That is what reserves are for. Just do not set one out of general anxiety.