I'm with you'r son, a very deep purple, about Pinterest Andre. Facebook has a horrible terms too, but most users never really read or understand them.
I'm not too concerned with theft anymore but am with permanent loss of the full size editable originals. In that way the "free" services are suspect except with the likes of Apple, Google, Amazon and maybe one or two other tech giants who are so large as to be permanently in the storage business and who make their money from other services, so where the server farm costs are vital to all aspect of their core business and where photo storage is a trivial extra bit.
I presume we are talking about both "how to" on the road, and also long term management so that we don't suffer massive loss of cherished memories, far down the road. I'd like to add a few tips and best practices as I work by, just in case it adds any value for others.
I think you advice to store in triplicate is golden and should be frequently re-inforced. I would go further and say that one should not just spread the risk among three locations, but also multiple types of storage. Don't in other words have it on three hard drives only, or three cloud services. Differsify. I have the bitter lesson left by technological progress and obsolescence. From 1989 to 2003 I was an enthusiastic videographer. I went with the latest standard and invested heavily in gear. The latest and greatest back then was S-VHS mini tapes. I had a Camera, two jog-shuttle head machines and what I thought was a smart back up strategy. Now I have a box of priceless memories, all on a format that is dead and where the only playback machines are half dead obsolete grear and which require a DAC and firewire. It's all to much and all to expensive now to try to get back, because I discovered in early 2001, that the old backups were full of snow from the degraded, de-magnitized substrates that they were stored in. And the warranty. Yeah that's a good joke now.
The same goes for all those CD's and DVD's that early digital photographers put their faith into. My first digicam was bought in 97 and of course backed up in duplicate to CD's - the expensive ones. I have a filing cabinet full of those. Four years ago I found that about 15 of about sixty that I transferred over to a Win 2012 server with multiple hard drives (for better retrieval) would not read. And as time ticks that shall get worse and worse. Heck, then there is the fact that only my two servers have a DVD rom I can attach and only one old Mac mac still has a DVD reader/writer. Obsolescence seems to sneak up and move quickly. It's a very good strategy to always engage multiple-format storage media, never just one type, no matter what the glossy web review rave about todays super-duper new way.
At home I like to ingest my photos on whichever machine I'm working on. Mostly that is on my mac Mini, but perhaps the laptop, or windows. It does not matter because I just ingest in to the local drive for grading in one of three ways. One star, two star or three. That describes "delete" "keep but likely never look at again: and "move to edit drive and backup media:. I key word them at that time and add basic metadata and just leave them there. A week or two later I look at them again - I find a bit of time helps me see things better, and make my final choices and then move them simultaneously to a raid 1, two drive external array and also to my main storage PC onto it's secondary drive(It has five internal storage drives as well as removable System drives so I can switch OS's. If for example Win 8 has a meltdown I can simlply slide out the Win 8 SSD and slide in a mirror copy, or my Win 7 or Win 10 SSD. That's how I deal with the uncertain parts of Windows, as well as the fact that the internet access to the Windows box only comes through another machines. If one wants to be able to do all this stuff, the moving, copying directory structures across multiple drives, keywording etc, in an easy and quick way take a look at Photomechanic. I can for example I can for example, with this one of a kind software, use the control button and press the number key 1-9 as I quickly look at each shot. This color codes each picture. Then with one keystroke the software moves the photos to different folders onto a second as well as at third drive simultaneously, changing the metadata of each and placing each shot according to it's category into their own folders, and duplicating exactly the folder structure, no matter how deep across multiple drives. Or for example, when we used to shoot Wera motorcycle races and other sports, this software allow you to type in the racers plate number, or an athletes jersey number - and presto "code replacement" changes that into the full name, address and contact number - for each person. It's a powerful time saver, and making things easy is the key to keeping up with good practice, I feel.
So once I've got this sorted I delete the originals from the local drive to free up space. Without going into more details I wind up with a set of original photos I deem worthy of editing, located on two portable external drive made slightly more robust via raid 1 and onto a second machine with multiple drives where the originals sit alone on one medium size (four terabyte) drive. This servers drive is backup up by a second machine (just this 4 TB) drive and saved on a (hardware controler) raid 1+0 four drive hot swap Proliant server. Or at least it used to be. A few years ago I decided to re-purpose this server for my virtualization lab, and decided that if I were to loose about 80 percent of my old "artsy" photos - I don't care. So I live recklessly and only have the photos spread across two systems. But the above appealed to my idea of "best practice" I do however keep this raw originals drive on a second drive, made identical bi-montly or so, which I keep in a drawer. I used to keep it at work for extra safety .. and should put it in a safety deposit box ... but I've gotten sloppy.
I could go into a rant here about file systems .. but will spare you all.
So then, these selects which I plan to edit get copied onto yet other drive, (my 2tb edit drive) and worked on. The final JPGs then get stored not a jpg's in folders, but on one more drive yet but rather inside a Capture One Pro database. This then gets periodically imported to horrid but easy to use piece of Apple software "photos" on a second internal Mac Mini SSD and shared out to friends and more importantly and finally - the cloud. The cloud I love, but don't fully yet trust, for all the reasons Andre has mentioned.
Now this is all easier in the doing instead of the telling, and it may come across as a bit overly paranoid. But oddly, just like tuning a bike to the best possible standards (or doing research and reviews of products as only Dan can do - it becomes more fun, for the care put in. In prectice it just hums along. And my photos used to be precious to me. Now not so much except those that have my family captured through all those phases of life, and they get taken care of in a more special way. One of the dark linings in the silver cloud of digial, are the huge volumes of photos we capture. It's easy to get overwhelmed if one does not stay ontop of it all before it becomes an unmanageable mountain. I of course, when working, losing just one folder of photos would possibly have cost me my job, so I got file management religion very quickly.
I have some more thoughts .. but I hope that this is a bit of a springboard to others sharing how they approach this important to us all topic. I'd love to hear other strategies. Now time to attend to the needs of the day.
A drawer full of (partial) "special moments" security.