Increasing quantity has no lower (or upper) bound (and gives a representation of negative numbers) vs. increasing quantity has lower (and/or upper) bound.
All left examples have a clear "zero" value, but it may be unclear which side is meant to be positive and which side is meant to be negative (See BP893left for quantities without clear notion of increase/decrease.)
CROSSREFS
See BP353left for looping quantities; these do not clearly represent positive and negative numbers, but they can likewise unboundedly decrease and increase.