Service limits
The GeoEnrichment service implements limits on users in order to guarantee accuracy and performance. The limits define the maximum size of a study area, maximum number of study areas, business records in an output, maximum drive time polygon size and many more. Exceeding these limits will cause your query to fail or be returned with a warning that you have exceeded one of these limits and will get results up until the limit is reached.
A list of service limits can be generated with the serviceLimits discover method seen below: Return a list of service limits that can be run using the GeoEnrichment service.https://geoenrich.arcgis.com/arcgis/rest/services/World/geoenrichmentserver/Geoenrichment/serviceLimits?f=pjson