Not Apple Friendly
Several months ago I had Bestbuy do a survey of my home wifi, and was told that the best was eero. I bought the basic package of 1 eero and 2 beacons and found my wifi was greatly improved. I touted it to several friends who also bought the eero system. While my wifi was very acceptable generally thoughout my home, it wasn't too great in my home office where I have a iMac. I thought that by adding another beacon in my office my wifi would improve. I added it this morning, and it didn't connect to anything, so I called support and was told that I should unplug all eero devices, then after a pause start by plugging back in the eero, followed one-by-one with the becons. I did that and the problem got worse. The eero captured about 13 devices and the other 3 beacons 2 or 3 each, most of which were nowhere near the attaching beacon. I called support just now, and was told when I described the problem that it is an Apple problem - the Apple devices will latch on to a beacon and not move. He agreed that adding the beacon to my office wouldn't solve my issue. Now my wifi is worse than before I added the new beacon, as the devices were fairly spread out among the 3 eero devices, although not necessarily near them. We are an Apple household - 2 iMacs, 2 Apple watches, Apple TV, 3 iPads, 2 iPhones. I don't know if any of the other mesh networks have this issue with Apple products, but I think that eero did not do me, as a consumer, about stating up front in their ads that Apple devices do not work well with eero
eero works fine with Apple products. I’m an Apple household too (and lots of other eero customers as well).
The way Apple configures their device’s WiFi profiles is to only change to a different access point at a certain signal strength level. This will happen regardless of what manufacturer of access point you have. There’s nothing eero can do to “force” your device to another access point. The way WiFi works is that it’s up to the endpoint device to choose.
If eero support didn’t tell you to try this, you can also turn off/on WiFi on the device/computer and then it will usually connect to the closest AP (since that AP would be showing the strongest signal).
Part of the issue that you’re having in your office might be that your iMac and/or your beacon has too weak of a signal back to another node. Did you try putting the beacon out in the hallway or another room close to the office, but still closer to another eero node?
Another mostly Apple home here (and problem-free after installing eero) and I can verify it sometimes takes overnight for stationary devices (any brand) to switch to their closest node as cotedan87 mentioned. Matter of fact, I found it pays not to make any judgments about the network's performance after making changes to your eero system for at least 30 minutes based on a tip from one of eero's developers. I assume it just takes a while for the mesh to reorient and make the best routing decisions.
Also, try running Health Check on your eero app. It can do amazing things maximizing speeds in a difficult or borderline environment.