PS3 is the clear choice for me.  It really did have a lot of great games in its library, and it also really did lose Sony a huge load of money.

Runner up goes to Colecovision.  There was supposed to be a distinct generation of consoles while the market was crashing which included Colecovision, Atari 5200 and Vectrex.  However, everyone expected Atari 5200 to be the successful console and it was a total turd.  Atari had a console successor much like the Wii -> Wii U situation.  Colecovision should have been the new market leader, but since video game consoles were such a new business, retailers panicked and just wanted to get rid of all of them.  Colecovision never got the chance it deserved. (I guess that also makes it kind of like the Dreamcast.)

How did the Wii U damage the brand when its successor is one of the best selling console ever? If the brand had been affected by its failure, the Switch wouldn’t be selling as well as it does.

Did the Wii U launch selling like the Wii did?
Did the Switch launch selling like it was going to become the best selling console ever?

Better question, was there any projection from a respected source that Switch would sell as good or better than Wii?  No.  The Wii U damaged that from being a consideration.  And it only launched somewhat decently because Nintendo combined home and portable.  Switch didn't just replace Wii U, it replaced the 3DS too.  

The Wii U caused massive brand damage both during its generation and leading into the Switch generation.  The pandemic meets Animal Crossing phenomenal shift was not predictable nor plannable. And without that gift from the VG gods, Switch would have been replaced by now.  However, had Switch had the brand power from before the Wii U, Switch would have started off breaking every record possible. 

And I haven't even mentioned the damage Wii U did to 3rd party publisher relations.  Where are the exclusive 3rd party games?  24 out of the top 50 best selling Wii U games are 3rd party.  5.5 games for Switch (1 is a crossover title).

Wii U only damaged Wii U. Wii itself that audience moved on to smartphones. Nothing was going to save the Wii U from itself. Switch was selling like hotcakes the moment it launched. There were more copies of BOTW on Switch sold at launch than systems sold. Switch didn't suffer from Wii U at all. Wii U suffered from a worn out label. Bad hardware and marketing. Plus Nintendo working on 2 consoles and outdated 3rd party relations. All of that was fixed with Switch. If you want brand damage look at Xbox One and Xbox brand never recovered.

I'd definitely consider Gamecube unsuccessful. 

It continued the decline in Nintendo's market share and mindshare, to the point where they abandoned power-competitive consoles altogether and went in a completely different direction with the Wii.

Do we actually know if it turned a profit? Nintendo themselves during the time did, but how much of that was due to the highly successful GBA?

Ah, another connoisseur of Colecovision, I see.

Colecovision is my choice for this, it was built on premise "play arcade games at home", delivered that, and came bundled with great port of Donkey Kong (which Coleco secured exclusive rights for). It was true beginning of 3rd generation (for doubters, SEGA SG1000 is considered Gen 3, and that has pretty much the same hardware as Colecovision, while launching a year after Colecovision, along with Famicom, which was greatly influenced by Colecovision). It had great initial success (which really worried Atari), but what killed it is its own company - yes, there was a NA video market crash, but Colecovision was doing quite fine - that is, if Coleco didn't bet on the wrong horse and funneled all their resources (and Colecovision parts) into home computers (seeing success of C64), with ADAM then releasing and being a massive flop, Oh, and that fucking Cabagge Patch Kids dolls, which were indeed massive success for them for a while - COLECO was, after all, COnnecticut LEather COmpany (it is a bit more complicated, but in the nutshell).

Market might've been quite different by the 1985, when Nintendo decided to dip their toes into NA home console market, if Coleco didn't kill its own console.

I'm gonna give a shoutout to the Saturn.

It had its faults, but its also got a scrappy underdog charm that's quite endearing, plus it has some really cool games like Panzer Dragoon 1 and Zwei, Radiant Silvergun, Burning Rangers, Powerslave, Nights into Dreams...

Whereas the Dreamcast gets a lot of love these days, the Saturn remains largely forgotten, which is a shame.

The Bally Professional Arcade, also known as the Astrocade, is an unsung gem of a system. Had the ability to be made into a full computer with BASIC. Its best game was The Incredible Wizards, a near arcade-perfect port of The Wizard of Wor. It came with Gun Fight built into the system's firmware.

I agree with you Curl.  I rented a Saturn back around 1995 for a week.  I liked Daytona, but didn't buy the system. A year later, my boss sold me his PS1 for cheap money.  I couldn't say no to his offer.  Also, at the time, I remember being a subscriber to EGM magazine and they gave a better review to the PS1 edition of Tomb Raider versus the Saturn one.

One more thing, do you guys remember the Neo Geo console?  I remember that one around 1994, it sold at the mall for something like $700 and each game sold for something like $150.  I couldn't believe any company would be crazy enough to charge such outrageous prices.  I knew the system was doomed.