Myth: turn off Microsoft Defender to make Windows faster — via Microsoft Support

MythNeeds adminWindows 11Windows 10

Turning off real-time protection in Windows Security is only temporary (it switches back on by itself), and while it's off, files you open or download aren't scanned. If Defender really slows down a particular job, measure it instead of switching protection off.

What to do instead

Find out what Defender is actually scanning: in an administrator PowerShell run New-MpPerformanceRecording -RecordTo C:\Temp\defender.etl, reproduce the slow task, press Enter, then run Get-MpPerformanceReport -Path C:\Temp\defender.etl -TopFiles 10.
If a trusted folder (for example a big code or build folder) is the culprit, consider a narrow exclusion for just that folder. Microsoft warns that exclusions reduce protection.

The performance analyzer needs Defender platform 4.18.2108 or later, and it needs administrator rights.

Sources

Turn off Defender antivirus protection in Windows Security — by Microsoft Support
Performance analyzer for Microsoft Defender Antivirus — by Microsoft Learn

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 Windows build, so keep the undo handy.

defenderantivirusreal-time protectionperformancemyth

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

Myth

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.

Myth: turning off Spotlight makes your Mac faster — via Howard Oakley, The Eclectic Light Company

Myth

Old tips say to switch off Spotlight indexing to speed up a Mac. It's a blunt fix that breaks search, and it doesn't work the way people think: switching off the categories in Spotlight settings doesn't actually stop indexing, and Howard Oakley found it can even slow some Finder operations.

Myth: you should run the daily/weekly/monthly maintenance scripts — via Ben Schwan, heise online

MythAdmin

For years, Mac 'maintenance' advice was to run sudo periodic daily weekly monthly, or let a utility app do it. Apple stopped relying on these scripts and removed the periodic command entirely in macOS Sequoia. Housekeeping like log cleanup is handled automatically by other parts of macOS.

Myth: turn off Microsoft Defender to make Windows faster — via Microsoft Support

What to do instead

Sources

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