You can follow every single best practice and still fail if you can't interact like a human being.
Situations like this are the extreme, but they reflect a more common approach to initiating discussions.
People respond to discussions because they want to:
1) Help the original poster (efficacy/validation)
2) Build a relationship with the original poster (affiliation)
3) Impress the community (positive distinctiveness)
When you initiate a discussion, it has to feel like it comes from a real person, with a real message, and a real impact.
By real person, we mean that you (personally you) feel like a genuinely interested member in the topic. People know you. You express opinions. You don't speak in the third person or only recite the brand's message.
By real message, people have to know why you're asking the message (how does it help you?) and why you're asking the message now (why not tomorrow?)
By real impact, if you don't respond or don't highlight how it might help you, people are less likely to respond in the future.
Here's one of our own examples that got a decent, quick, response.
This post gets a decent response because of three reasons:
1) I have a history of participating, plenty of relationships with members, and express my opinions in the past. People know who I am. They (hopefully) know I'm not a corporate drone.
2) The post explains I'm asking the question. How it helps me and why I'm asking the question now.
3) It specifically asks people if they have tried it (everyone can respond yes/no), whether it worked, and if they have any other broader thoughts. They know what sort of response I want.
There are other tips here too. Keep it short, use short sentences, simple words, break long paragraphs into separate lines to make it more readable.
However, if you get the basics right, you're response rate should be much higher.