Why we did so:
Classic mailing lists have become a problem, because of free email accounts. These accounts are not fee at all. You pay with your privacy. They can find out your operating system, monitor size, GPS location, what items do you write about, what are people do you know, etc. They store each and every email you send or received ever since, and delete nothing.
From this data base, they can extract any data whatsoever from texts and documents, with algorithms which get stronger every year. I regard it a threat. Google can already recognise random persons from an unknown picture. The police can not do it, but Google can. Also they can recognise any building on earth, via their picture data base. So even when the GPS location was removed on purpose, they can still recover this, if a building is on the picture. Also, they can recognise total strangers on a pictures you made. You can not, but Google can! When you appear on a tourist picture somebody takes, and this somebody uses Gmail or the free cloud at Google, they can see it's YOU, an when and where, and who else was on that location that day.
If you don't believe it, make a picture search at Google here, at the picture search, and search for your own picture. You will find yourself all over the internet, and this part of the public data. Their non-public data, is many times larger, even indirectly they store information about you which is forbidden to store directly. Like when a website sends you a new password, Google should not save this, but they just save the email (for ever) and they also have it (for ever).
Even if you never send a picture of your face to Google, they already have it when you use gmail. There is always this one person appearing on most pictures you SEND which is not on most pictures you RECEIVE, and that person is probably...you! This just one thing of 1000's they do.
Also they live from payed service, to let items pass your spam filter. At the same time, they block news letters from others, because it's competition. So we have moved to Twitter for this, where things work more friendly.
Using 'free' Email is one of the largest mistakes there is. Your internet access provider normally offers a free email account with them, and this is the best place for such an account.