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How often do you clean install macOS?

hwut said:
Anyone else old enough to remember installing an OS from floppy disk?

Sitting there for hours, ok it's finished with this disk, remove the little 3.5" thing, insert disk 37 of 64, hearing the click and the whir as it spooled up and oh no, disk 37 is corrupt. Game over.
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Yes, many of us are old enough to shudder when we see the words clean install in the thread title. Not only were there boxes of floppy disks, updated patches and drivers needed to downloaded over slow modems back in the days when people usually only had a single landline and nothing else.
 
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hwut said:
Anyone else old enough to remember installing an OS from floppy disk?

Sitting there for hours, ok it's finished with this disk, remove the little 3.5" thing, insert disk 37 of 64, hearing the click and the whir as it spooled up and oh no, disk 37 is corrupt. Game over.

Sh*t is so easy these days, if I hear a younger coworker complain about their phone or computer I think to myself "bub.. you have NOOO idea .."
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Maybe I’m a bit too young but I do remember using floppy drives. Not to install an OS, tho.

I grew up with CD-ROMs, which still makes me old but not as much.
Ditching optical drives was a blessing, and currently I only use tiny external SSDs. With my new M4 Mac mini, miniaturization and minimalism have reached a new peak for my digital life.
 
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I'm not old enough to remember floppies being used for the OS, but I do remember CDs. The very first upgrade I ever did was Windows XP when I was about 18 years old. The first Mac I got came with 10.2, but I do remember the Panther upgrade DVD and going to to CompUSA for the panther launch party. Those were the days.
 
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hwut said:
Anyone else old enough to remember installing an OS from floppy disk?

Sitting there for hours, ok it's finished with this disk, remove the little 3.5" thing, insert disk 37 of 64, hearing the click and the whir as it spooled up and oh no, disk 37 is corrupt. Game over.
Click to expand...
That was aggravating. The Windows installer would say "can't read disk, retry?" but Mac OS would immediately abort.
 
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Already done when I purchase a new device . . . after that, I just update.

Update to relative Majors, for the most part; but, I have been known to do a Clean Install on occasion (love my '06/'12 MP's)

As with all matters prophylaxis, this is a *cough* personal Use-Case-Scenario-Dependent decision ;)
 
I set up a new Mac manually instead of using Migration Assistant, so I have a clean new installation every time I buy a new Mac.

However, I don’t do a clean install during the lifetime of a Mac: too much trouble, too little benefit.
 
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Nermal said:
Erase Assistant. It's functionally identical to a clean install.
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It says that it erases all the volumes but, I guess the volume where macOS is installed isn’t erased…

If there’s some kind of minor corruption in the operating system, the only way to fix it is by reinstalling it. At least that’s how it works on iOS. Sometimes if you don’t DFU your iPhone and restore it using the Mac, the problem isn’t solved. What would be the equivalent of “restoring” the operating system in the Mac?

As far as I know, that erase assistant only deletes the data volume, not the OS one, correct me if I’m wrong.
 
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Populus said:
If there’s some kind of minor corruption in the operating system, the only way to fix it is by reinstalling it.
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True, but recent Macs (include all M chips) will check the OS when powered on, and won't boot if it's corrupt. That's the only time you need to actually reinstall. If the system boots, then Erase Assistant will do the job.
 
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I've only installed MacOS from scratch once, when I replaced the failed SSD on my 2008 or 2009 MacBook Pro. The other dozen or so have never been reloaded, with the exception of a 2010 iMac - but it was reloaded with Ubuntu, since that machine can't run anything even kind of recent from Apple.
 
Never have. I just install the updates as they come and leave it alone besides that.

Up until about 2 years ago I would do yearly windows re-installs though, which sometimes were caused by the install rotting and sometimes were just me wanting to clean up my drive from useless program files.
 
So, I have had my iPhone 14 Pro since April 2023 and have been simply updating iOS on the OS that came installed with it. Yesterday, I clean installed/restored my iPhone for experimentation purposes.

Prior to the restore, iOS 18.1 took up 11.2 GB as per the Settings app. After the restore, it was 11.19 GB. So practically the same. System Data before the restore used to hover between 6-8 GB. After the restore, it is now 1.07 GB. This is after manually installing my apps and setting them up. I didn't restore from a back up but setup the phone as new.

The phone now seems snappier and apps launch noticeably faster. My eSIM was was not deleted during the restore and was there in the Settings app once the restore was done.
 
Every 2-3 years. It makes the Mac noticeably faster.

I store everything in iCloud, so formatting the SSD is no problem at all. I use the machine casually, so the setup is minimal as well.

I believe something happens with Mac OS after 2-3 years, it fails to fully clean itself. It just becomes more laggy without a good reason. A clean reinstall fixes that.

It might all be Voodoo and placebo effect, but I do notice the difference.
 
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ProQuiz said:
Is cleaning installing macOS 15.1 and then updating to 15.2 the same as clean installing macOS 15.2? I've been told that every macOS/iOS update is treated and done as a "clean install" (at least the OS partition). So there would be no leftover OS files or remnants from the older version when updating to the newer version?
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This is only true once Apple split the OS into its own partition, right around the same time as APFS. It was absolutely a good thing to do prior to this happening.
 
Andrey84 said:
I don't think it's functionally identical to a clean install.

Clean uninstall involves fully formatting the SSD.

Erase Assistant only deletes users' data and settings - it doesn't delete the Mac OS. It's the same function as in the iPhone.
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My argument is that deleting and reinstalling the same data is equivalent to leaving it there.
 
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A clean install might still be a good thing to do, sometimes.

I quote myself from this thread:

I mostly use Migration Assistant, but once every few years, I choose to setup my whole mac from scratch. Often when there are big changes, like a big jump in macOS versions, big change in hardware, changes in users, what the mac will be used for etc.
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Yes, the SSV system volume is completely rewritten on any upgrade, but you might have old software, maybe outdated kernel extentions that might be problematic, and they continue to stay on the '- data' volume unless you do a clean install and start from scratch. Migration Assistant will also keep old, possibly problematic stuff.
 
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Depends on the computer. I wipe my iMac at the end of every school year before I throw it in storage for the summer. When I had my M1 MacBook Air, I never reinstalled macOS.
 
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