Why do methods not return error?

[swdee]

The methods of this package don't return any error, such as in the Set() method;

https://github.com/VictoriaMetrics/fastcache/blob/8835719dc76cc26f97026e3aa726742e7d2f1053/fastcache.go#L145-L149

Which in turn calls the buckets Set() method that silently skips caching entries at lines;

https://github.com/VictoriaMetrics/fastcache/blob/8835719dc76cc26f97026e3aa726742e7d2f1053/fastcache.go#L308-L312

https://github.com/VictoriaMetrics/fastcache/blob/8835719dc76cc26f97026e3aa726742e7d2f1053/fastcache.go#L319-L323

Is there a design decision as to why these methods don't return an error?