There is no such thing as a continuous market. Everything, even stocks that are being traded at a high frequency, has moments when it is not being traded. If

There is no such thing as a continuous market. Everything, even stocks that are being traded at a high frequency, has moments when it is not being traded. If continuous markets were somehow realized, then moments when value is "missing" per your definition could be rare. But instead, there are infinite non-trading moments between each pair of trades, so "nearly all" of the time your definition says an asset is worthless. That just seems like a useless, inappropriate definition from a practical perspective. https://en.wikipedia.org/wiki/Null_set https://en.wikipedia.org/wiki/Null_set