Responsiveness refers to how well data responds to the current rates. If the data is too old its less responsive.
Stability refers to how credible the data is. If the size of data is big, then we can rely on it as the larger chunk of the data is already known and even if the unknown chunk has outliers, it cannot distort the average effect of the larger chunk.
To get responsiveness, we need recent data, but recent data is incomplete. To get stability, we need complete data, which is mostly found in old data, but old data is not responsive.