Users build up expectations about how applications should work based on the applications they're already familiar with.
If you're including a search box in your application, it should work as much as possible like Google. Even if you have some clever idea about how it should work, if that way makes it act differently from Google, that's probably enough of a reason alone not to do it. We'll make the terms they typed in automatically match an exact phrase because our users would probably like that! Nope! They won't because Google doesn't do that.
How will we let users know that there's fresh content for them to see under a tab of our application? Hmmm...got it! Let's underline the tab title! Wrong! You put a little dot to the side of the tab title, because that's what every app your users are familiar with does.
An invaluable skill for product owners, product managers, business analysts, etc. is that they are widely familiar with popular software and applications. And more importantly they are able to map requirements for the product they manage onto the conventions of other existing software.
Please, by all means, if you're a startup building a general purpose search engine from scratch, go ahead and wildly violate the conventions of Google search. That's literally why you exist. But if you're building a search box for your forklift parts website, make it work as much like Google search as you possibly can.
If you're building a feature for your accounting application where a user can send another user a message, this is not the time to innovate. Just make it work as much like Slack, Instagram, Twitter DMs, etc.
I feel like well-meaning product managers sometimes misunderstand what innovation means in software. Innovation in the realm of what I would call commodity features is not good for your users. Features that are present in many applications are not the place to innovate unless that feature is at the heart of the value proposition of your application--if your product is that feature.
Wow...if you're violating users' expectations about a commodity feature in your application, you better have a damn good reason. Everyone else: make your thing work like the thing everyone already knows.
