Are values of timeseries with reporter=source and reporter=destination supposed to be equal to eachother?

I have 2 questions regarding telemetry

From documentation:

Reporter : This identifies the reporter of the request. It is set to destination if report is from a server Istio proxy and source if report is from a client Istio proxy.

When I create a svc and access it from outside the cluster, I see there are two timeseries created. After hitting the endpoint from outside several dozens of time, I see that metric istio_request_duration_milliseconds_count gives two timeseires whose value are sometimes the same. The two series differentiate in reporter and pod_name labels.

My first question is are these two time series supposed to be the same - i.e. it doesn’t matter which we use to report.

The second question is why do the timeseries with label reporter=‘source’ only appears when I hit from the outside? If I hit the endpoint from a pod within the cluster, I only have the timeseries with label reporter=‘destinaion’.