Why so many Flaky Buyers?

I have had multiple experiences of buyers who respond to ads for items I have for sale who do the following:

Say they want to "move on this sale", "I'm interested in buying it", and then never respond when I email them back, asking for confirmation of the deal.

I have had numerous 'buyers' who ask "Is is still available?" and then never email back.

Buyers who say in their initial email that they are very interested in the piece, then later say they are not sure what they want to do.

Buyers who insist on lowball offers on a piece advertised as firm, trying to shave hundreds of dollars off, and get free shipping as well.

I'm honest, straightforward, amiable & accommodating, so I see no reason for this.

I'm really sick of this, and wonder if this is a common experience others have.
Hello Kevziek: You have received some good responses to your post here. I would add that the seller has committed to selling an item at a certain price, while the buyer can fall into two categories; those who know exactly what they want and what they are willing to pay, and those who are looking for a general item (i.e. a preamp) and would consider several different pieces, depending on the price and their subsequent research (including asking the seller questions). Also, keep in mind, many buyers do not have the opportunity to actually hear the pieces they are interested in, and rely on reviews, posts on sites like audiogon and audio asylum, and asking questions of sellers. I have found it pays off to be patient with questions, and to try and make sure the deal will be a win-win situation for both you and the buyer. On this basis, my experiences have been good.
A buyer has the right to ask for a price that he will pay. He has the right to change his mind, before a sale. He has the right to waste your time, as you have the right to sell to whom you choose. Just as you cannot make ALL sellers accurately describe their goods, you can not make All buyers, accurately convey their intentions.
Welcome to retail. While the internet has enabled us to buy gear at prices we never dreamed of, the downside is the quantity for sale. There are so many choices you cannot help but run into "shoppers" who are not fully committed to any one item. That is why you get so many "still available" inquiries. I try to limit the amount of tire kickers by posting "serious only please" but it still doesn't get rid of the "are you the original owner? how long have you had the piece? does it have this (insert whatever) when the same information can be gleaned from the manufacturers website, why are you selling?" and it goes on and on. All questions, which in my opinion, have nothing to do with anything. All part of the selling process I guess. I do get annoyed with the lowball offers (20%+ off the market price) and then want you to pay shipping on top of it. I usually tell those people that with their generous offer I will even load the piece in my car and drive across country to deliver it. You just have to take the good with the bad.
Fletch, i'm sorry but i'll have to ask you to leave. Your response is WAY too level-headed and realistic for you to be an audiophile. As such, we have no room for "unbelievers of the mystical arts of audio" : ) Sean
Great responses so far. I would add that there are no widely accepted rules on how to buy/sell on the internet -- it's not something that is taught as part of our culture or growing up -- it's so new. Over time, that will straighten itself out, and there will be more "rules of the road" or commonly accepted behavior. This pertains particularly to the time lapses of the net -- there have been plenty of times when I've asked questions as a buyer, gotten a response, made an offer and was then told that the piece had been sold. Should a buyer complete the transaction with an interested party "in dialog" before selling to a new party? Maybe. What are the right ethics here? Ditto for someone saying "I'm interested" and then buying it somewhere else before the dialog has been fully completed.

I'm with Lancer -- if a commitment has been made, the dialog should be over. But until there are clearer codes of conduct around how to handle the time lapses of dialogs, both buyers and sellers will sometimes suffer. My two cents. Thanks.