When are buildings abandoned?

Roads are the key. Roads need to connect residential buildings to service buildings. And of course you need enough services to support the number of residential buildings you have. 1 residential building = 1 capacity/demand.

You need to have enough power, water, sewage, waste management, and fire/police/health coverage.

Traffic affects population and happiness too.

Pollution is another factor.

Residents also dislike living near certain buildings like government (City Storage etc).

Quite often you can tell why residents are unhappy because there's a bubble above the building.

"Are you going to build a power plant or what?"

"I smell smoke..."

"Service Disabled. Reason: No connection to road"

etc etc...

Yeah, there are many things that are immediately affecting happiness. However, I've found that unhappy citizens does not necessarily mean they abandon their home - I can drop below 10% overall happiness by removing all supply buildings (power, water, ...) from the streets. Everyone tends to get unhappy, no one will leave.

If I connect the supply buildings again, happiness will rise, and the first people are going to leave as soon as total happiness is above 15% - but for completely different reasons, such as missing police coverage.

Can anyone confirm that? Different observations?

If you disconnect the road from all services, they move out immediately. I just deleted all my residential roads and my population immediately dropped from 2.6 million to almost 0.

When I created all the roads again, my population was immediately around 1.6 million, and as happiness rose from about 10%, my population increased.

I think when my happiness was back to 55%, I had 2.3 million people. 100% is back to 2.6 million.

If you only have a problem with 1 service, it's only the excessive buildings that are affected, and not to a great degree if all other services are functional.

Interesting! It seems like this is somehow tied to the player level. With my current account, I'm at level 14, and friends of mine at lower level never have heard of citizens moving out. May I ask what level you're at?

That city is level 55. Too bad I didn't take a screenshot. It's a pain doing it again because when I delete the roads, many parks move around and block the path where I need to rebuild.

I just tried the same thing on my level 19 city. As soon as I delete a road that connects a residential building, the population drops immediately. I deleted 1 road and the population immediately dropped from 159k to 140k. I rebuild the road, and the population immediately grows back to 159k.

Residential buildings display "Abandoned Buidling. Reason: No connection to road". Those buildings have 0 connected services without the road. I think if the road was there, but some services were affected, then only part of the residential population would move out. I would have to build more to see that happen.

Yeah, disconnecting a residence from the street network makes everyone move out immediately. I've tried moving the other buildings away instead (power plants, ...), which caused a happiness drop without citizens leaving. Re-connecting the power plants caused the happiness to rise again, and (oddly) eventually causing citizens to abandon their homes due to other unsatisfied needs (such as police).

Building (citizens abandoning)

I've noticed this in SimCity as well. After a decrease in happiness then an increase they leave. I think it has to do with new citizens and the current satisfaction with the mayor. I noticed after a few times that if they dislike me then I correct the issue they leave. I suspect that it due to the new citizen overall new level of satisfaction that's also a reflection of what my popularity is , and as a mayor, have done in the past. It reflects on my stature. If they like me, my rep goes up with it. If I screw up they dislike me and they leave. Not saying this is right in a game but it funny to see this take affect. I've witness a downgrade in respect overall when I mess up. it's actually harder to regain their resect once I fail to keep up with demands.

If I want a product and you as mayor provide it for a while then take it away, I get angry. If you, as mayor, bring it back, it's like taking it away from me then giving it back. I ask myself why take it away in the first place? It just make me hate you even more. I need something and your messing around with me. just like it says in SimCity when you plop a church don't destroy it.