I believe some caching is used and that that it doesn't update all occurrences of the same data calls at the same time, and thus the profile version may still be outdated for grabbing the data from cache where the chart version was up-to-date. And since the charts change quickly I can imagine that the system forces to fully update that more regularly than profile pages.
Not sure if this is the reason, but being a coder myself, that is the reason that makes most sense to me.