iMac updates

There are factors:

1 - Like poor Wifi connection

2 - Slow wifi connection

3 - Too many other people downloading at the same time and Apple Severs are overloaded

4 - Software on the computer interfering with the download process including AntiVirus Software

Notation: Disabling the AV Software may or may not solve the issue. Removal of the AV Software may increase the chances of the download to perform as expected.

5 - Running behind a VPN which may increase Packet losses or corruption of the download 

6 - If via wifi too many Other devices using the wifi at the same time reducing the Bandwidth to your computer. 

7 - Best Results are via Ethernet Cable to Router

8 - Restart in Safe Mode. This will perform a Disk Repair, clear cache files and only load Apple Software, extensions and fonts. The boot up will be slow and can take some time - Normal and Try Again using the Software Update Applet in System Preferences

9 - Worst case - Restart in Recovery Mode and choose Reinstall macOS. This in theory will pull the latest version of Monterey available and commence the installation.

Hi,

Try booting into Safe Mode: How to use safe mode on your Mac - Apple Support and see if the issue persists there.

My iMac 27 inch late 2014 does the same thing, A few weeks ago in actually downloaded an update but now it just stalls while looking....