Most sales fail long before you have the sales call.
They fail because you've not set the expectations correctly.
They fail because the client doesn't believe that there's any urgency to getting involved.
They fail because the client doesn't fully understand why they need your service.
If you look at LinkedIn (please connect with me - I do a lot of good stuff on there), you'll see a lot of people have a headline in the form "Helping X achieve Y through Z". For example, "helping redheads achieve mindfulness nirvana through 3d printed furniture".
This is a positioning statement - it explains, in one sentence, who your ideal client is (redheads), the problem you solve (mindfulness nirvana) and how you solve it (3d printed furniture).
If the potential client doesn't feel like they're not a good fit, that what you offer isn't what they're looking for or that the way you solve the problem doesn't work for them - then the sale has gone wrong before you even begin.
They might sound genuinely interested - matching two out of the three criteria means you will have an extremely compelling conversation with them.
But not fitting your positioning exactly removes all urgency from the client's situation. They will just have a nagging doubt in the back of their mind, which translates into "I don't actually need to act today, it can wait".
But even if your positioning is perfect, there's one more reason the client may ghost you