Hi, first post on these forums

I have a question about Fallout lore and was wondering if anyone here knows the answer.

So there are these Vaults, right, built by Vault-Tec for the official purpose to protect US citizens in the event of nuclear war. Now, the wiki states, and the game supports this, that the "true" purpose of the vaults was to perform social experiments on the vault dwellers, and that Vault-Tec (or the US govt) never really expected a nuclear war to happen. Now what I don't understand is the following: if Vault-Tec didn't expect a nuclear war to happen, and built the vaults only for experiments, how did they expect to get any people into the vaults to do their experiments on? I mean, if there's no nuclear war, people won't go live in a vault. Conversely, if Vault-Tec did expect a nuclear war and built the vaults to protect citizens and allow the human race to survive, then why did they do all kinds of dangerous experiments on them? I mean, it seems kind of risky to perform life-threatening experiments on (possibly) the only samples of humanity you have left.

Can anyone shed any light on this?

Vault-Tec probably never expected a nuclear war and just made it seem like there was going to be a nuclear war, people then belived them and entered the vaults. Some time after the vaults had been closed karma hit.