Polkadot - Mobile & Chrome wallet (polkadot.js)


are here anyone familiar with Polkadot wallets? I have a (probably) a newbie questions…

I have created a mobile polkawallet on my iPhone. Then i created polkadot.js wallet for Google chrome. I clicked on “import account from pre-existing seed” where i have put in a recovery phase (12 words) for my mobile Polkawallet. So far so good. Account was found - public address is matching to the address on mobile Polkawallet. I compared the addresses for Polkadot and Kusama network. They were both matching.

But what bothers me is that for Polkadot.js wallet i typed in a different password that i am using for mobile Polkawallet (this happened by accident) but i was still able to login into my Polkadot.js wallet even though i typed in a wrong password.

I made a research and find out that password is actually used for confirming the transactions out of the wallet and not the actual login because supposedly you are always logged in.
Is that true? To me it`s a bit strange because with Metamask i always log-out and when i want to use it i log-in and type in a password.

Also i find it strange because i changed my password with such an ease. The system didn`t even asked me for my old password. I just accidentally typed a different password and system just let me through. Is this fine? I am a bit confused to be honest and my first feeling is that Polkawallet is not as safe as Metamask wallet…

Also is is true that you must have at least 1 DOT on your wallet otherwise system recognize it as inactive wallet and it delet`s it?

Thanks for your help and have a nice day.