It's unlikely Google drops projects any more frequently than startups fail. I have (or have had) a lot of paperweights manufactured by failed startups, so I know it happens. I'm sad when startups fail, but they usually failed for the right reasons. It doesn't taint my overall perception of the startup concept.
If you think the Nexus Q was a fantastic product and that Google made the wrong decision to kill it, that's one thing -- you're saying they have bad taste, or bad product sense, or an inverted sense of quality vs. crap. I wouldn't agree with that assessment, though I admit it's an valid, internally consistent opinion.
But it's more likely you never owned a Nexus Q and are just using it as an example of how projects at Google get killed. Sure, Google kills projects. Just as startups fail. That's no more astute an observation than saying that sometimes it's sunny and sometimes it rains. You wouldn't expect Google to keep funding a stalled or not-quite-thriving project any more than you'd expect investors to keep plowing money into a startup that can't find product-market fit. Sure, the opposite outcome sometimes happens. But generally it doesn't, and that's OK.
Some think Google is valuable because it takes more risks than companies its size. The implication of your opinion is the opposite -- that Google should be more risk-averse (not starting this router project because a router is a crazy thing to build), or innovate more slowly (launching it later than today because it's not ready), or ignore market feedback longer than a startup would (damn the torpedoes, it sucks and nobody wants it, but let's keep its team on a death march). Is that how you'd run Google if you were its CEO?