For a startup an example objective would be an MVP launch and a key result would be an MVP being tried out by 10 people in a coffee shop, or getting 100 views from various blog posts. Something like this would set an expectation for the whole team (sales, marketing, engineering...) for the quarter. It shouldn't be complex, but it has to be something well thought out and serious.

I would get crazy if I would get a new strategy every 24 hours. The details of the execution can change, but the objective and the key results shouldn't change that often.