In this scenario, the 'inode' limitation is the likely cause because a filesystem can run out of inodes even if there is available disk space. Each file and directory requires an inode, and if there are a large number of small files, the filesystem can run out of inodes before it runs out of actual disk space. Understanding inode limitations is crucial as it is a less obvious reason for 'disk full' errors that does not directly relate to the physical storage space. Overprovisioned IOPS could lead to performance issues but would not cause 'disk full' errors. Fragmentation could slow down file access but would not cause 'disk full' errors if there is still space available. Filesystem corruption could potentially cause 'disk full' errors; however, the monitoring would likely show discrepancies in available space due to corrupted data, not just unexpectedly generate errors.