I think its more like trying to find the highest mountain in a range of mountains, except there's too much fog so you can't see how high other mountains are com

I think its more like trying to find the highest mountain in a range of mountains, except there's too much fog so you can't see how high other mountains are compared to the one you're on, so you can't tell if you're on the highest mountain until you've climbed them all. A lot of the non-quantum heuristical approaches leave you isolated on one of a few mountains (local maxima), because simply climbing back down and hoping to find another peak is computationally expensive and you know it will lead to a lot of suboptimal solutions before finding something hopefully comparable or even better than your highest peak reached so far.