Unbounded Label Values

As presented in Prometheus [Metrics and Label Naming](https://prometheus.io/docs/practices/naming/#labels):

> CAUTION: Remember that every unique combination of key-value label pairs represents a new time series, which can dramatically increase the amount of data stored. Do not use labels to store dimensions with high cardinality (many different label values), such as user IDs, email addresses, or other unbounded sets of values.

This is critical for Prometheus performance, with impact in both storage and memory consumption.

Speaking specifically of the label `errorMessages`, wouldn't it be healthier to classify errors into something more _characteristics-prone_ (as database|network|business)?