Myth: your Mac needs a 'cleaner' or 'optimizer' app — via The Safe Mac

MythmacOS 14 Sonoma and later

Cleaner suites promise a faster Mac by deleting caches, logs and 'junk'. Caches exist to speed things up, so deleting them usually makes things slower until they're rebuilt, and deleting logs makes problems harder to diagnose. A Mac doesn't need routine cleaning.

What to do instead

Skip cleaner and 'optimizer' apps.
To free disk space, open System Settings > General > Storage and work through the recommendations, or move big files (videos, old projects) to another drive.
Keep plenty of free space on your startup drive (the article suggests at least about 10%) and review which third-party apps you really need.

The Safe Mac's view: caches only rarely become corrupt, and repeated cache problems point to an underlying issue that deleting caches just hides.

Sources

The myth of the dirty Mac — by The Safe Mac

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

Oddbyte.Me hasn't tried this on every macOS version, so keep the undo handy.

cleanercleanmymacmackeeperoptimizercachejunk filesmyth

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