Explanation
The complication is that every platform defines a view differently, and several have changed the definition. A view counted at one second and a view counted at three produce wildly different CPVs for identical delivery, so the metric is only comparable within one platform over a period where the definition held still.
Where it is genuinely useful is in comparing creative on the same placement. If two videos got the same spend and one produced twice the views, the difference is the creative, because everything else was held constant.
The common mistake
Comparing CPV across platforms. It is measuring different things under the same name, and the resulting comparison is meaningless in a way that looks entirely legitimate in a spreadsheet.