Tyler: Model 005 Early Access (Giveaway + Self Promo)

There shouldn't be game-breaking bugs, yes. But if a story turns out really good, you might play the game until the end, though the gameplay isn't that interesting or is partially bugged. Extreme examples might be visual novels (for me esp. Telltale) and walking simulators (e.g. Dear Esther, Journey) which don't provide real gameplay, but atmosphere and story can keep it interesting nonetheless.
Another example would be with franchise games and fandom. If you're fan of it, you probably try it out, though the gameplay is broken in the worst case. Personal example is Kick-Ass 2 , which I tried, though there were very negative reviews. And yeah, I didn't complete it.

What if it's a walking simulator with an amazing story?

Not necessarily. Spec Ops: The Line has some really generic gameplay and the shooting really is not fun, but the designers realized that they just did not have the budget to produce a really smooth shooter so they focused instead on creating a really great story.

In fact, it could be argued that the fact that the gameplay was not very fun to play through actually enhanced the worth of the game.

I would suggest watching these Extra Credits videos on the game to understand what I am talking about: 1) https://www.youtube.com/watch?v=kjaBsuXWJJ8 2)https://www.youtube.com/watch?v=cJZIhcCA2lk