I've recently seen repeated failures with edit conflicts, e.g.
INFO ## Signal: http://www.wikidata.org/entity/Q19718090
INFO Falling back to tags
WARNING Limiting Q19718090 to 300 of 1158 tags for performance reasons.
WARNING Invalid version strings in tags of Q19718090: ['v', 'v4.51.2-corrected']
WARNING Limiting Q19718090 to 100 of 300 stable releases
INFO Setting normal rank for 6.0.1
INFO Setting preferred rank for 6.3.2
INFO ## Signal: http://www.wikidata.org/entity/Q19718090
WARNING Limiting Q19718090 to 100 of 233 stable releases
INFO Setting normal rank for 5.62.0
ERROR Failed to update http://www.wikidata.org/entity/Q19718090: failed-save: The save has failed.
[messages: [{'name': 'wikibase-api-failed-save', 'parameters': [], 'html': {'*': 'The save has failed.'}}, {'name': 'edit-conflict', 'parameters': [], 'html': {'*': 'Edit conflict.'}}];
help: See https://www.wikidata.org/w/api.php for API usage. Subscribe to the mediawiki-api-announce mailing list at <https://lists.wikimedia.org/postorius/lists/mediawiki-api-announce.lists.wikimedia.org/> for notice of API deprecations and breaking changes.]
I've recently seen repeated failures with edit conflicts, e.g.