Yeah, but some story modes can be completed in a few minutes, or even less than an hour.  While other games can take 6 times that much, or longer.  It's almost like cheating to say you've finished a game that fast, yet you have no idea about the fundamentals of spacing and poking.  I've spent so much time playing Tekken Tag Tournament 2, that my playtime has hit 999:59:59, twice, since 2012, and it is still my most played game, racking up no less than 10 hours a week.

Do I consider it completed?  No, of course not.

But, when Tekken 7 comes, it will be done with.  Only to come back to once in a while, partially for the Tag battles with friends.  However, when I get used to the Tekken 7 movelists, there will be no going back.

Completed and finish are two different things in the gaming world though, especially with the creation of trophies and such.

For example I finished Watch Dogs 2, still have 3 trophies to get though, so I haven't completed it.

Also with your story mode time examples, since I am an RPG player, anyone playing a FPS game and counting that as finished by doing the campaign is almost like cheating as well since they only took 10 and not 70 hours to do it.  Not a realistic metric.

Can't remember everything by name but around 80 games.

Titanfall 2
Uncharted 4
Killzone Shadowfall
Battlefied 4


Games that don't really count
Driveclub
Overwatch

I probably need to keep track, I think I beat around 10-15 games?

Idk I'll keep track in 2017 but I mostly just played halo 5 so it's not high like I beat a few telltale games almost done with Titanfall 2 mostly done with BF1 and Infamous Second son and a few others I can't think of off the top of my head

Let's think. In no particular order:

3DS:
Mario & Luigi: Paper Jam
Fire Emblem Fates: Birthright
Kirby: Planet Robobot
Pocket Card Jockey
Hyrule Warriors Legends
Pokemon Picross
My Nintendo Picross: The Legend of Zelda: Twilight Princess
WarioWare: Touched!
Donkey Kong Country Returns 3D
Resident Evil: Revelations

Wii U:
Shantae and the Pirate's Curse
Deus Ex: Human Revolution - Director's Cut
Freedom Planet
Xenoblade Chronicles X
Shovel Knight
Affordable Space Adventures

Xbox One:
Gears of War 4
Destiny
Final Fantasy XV

Just two. Uncharted 3 (PS3) and Call of Duty Ghosts (PS4)

Doom
Uncharted 4
Ratchet and clank
Murdered Soul suspect
Transformers devastation
Last of us remastered
Dishonoured remaster
Rise of the tomb raider
Order 1886
AC syndicate
Pikmin 1 NPC
Mario 64

Assassins Creed Syndicate and Titanfall 2 are the only games Ive completed in 2016. Played a whole lot of Rocket League though.