Typically when things don't close, it's a buyer or seller digging in. I try to avoid this as best as I can by making sure everyone involved feels their opinion is being valued by the other side. 

It's rare we get under contract and don't close. But I guess the biggest is inspection issues.

It's rare but a really bad inspection can kill a deal.

When things go south, it's usually some emotional snafu.  I once had a love seller totally lose it because the buyer's agent made a big deal at settlement that she didn't think his cleaning lady had done a good enough job and the place was filthy.  It wasn't.  He had gone way beyond the "broom clean" required by the contract and he just lost it.  Her clients and I were looking at each other like "What the. . .?"  It did settle.  Barely.

working with clients who aren't motivated. 

Nope, I use an excellent Lender and between us we get the closing done.

 No, I am usually very good at seeing clients begin and close their side of the transaction. I did have one buyer who withdrew their offer this year when the seller decided to make their own electrical repairs instead of hiring an electrician like we asked. The problem was they lived in the home for 10 years with the issues.  My Buyer did not think they would do the repairs correctly for someone else if they wouldn't do them for their own family.

Inspection or lender issues.

No.

Inspections.

I don't have many deals that I write (or receive) that die, but if they do, it is at inspection.   Some are not really for inspection issues, it was because the buyer wrote on several homes to secure one.

Since June 2011 we've closed every deal, including Short Sale listings.  Some require more effort than others to drag across the finish line.  The most effective tool to make that happen is to make the Buyer's Earnest Money tough to retrieve (in the contract) should the Buyer misbehave.  

No, 99.9% of my contracts close. The times they don't have no commonality.

Communication skills of some real estate professionals and loyalty of some clients ( because another realtor/relative got involved). 

While I have only had close calls on a falling out they most commonly start with assumptions.  Something that should have been written, or something that was not written and assumed.  Clarification in writing a must.  Mark

Cayla Langhammer I have closed almost every deal that has agreement completed.

The only one that did not go through was due to mortgage commitment.

If we stay on top of the transaction, it is perfectly fine to expect that deal will CLOSE.