In a previous "Seller's Market", if a contract with the first Buyers fell through, nobody on the Seller side cared or worried: They would just release the contract and most probably negotiate a better price with the next "backup" contract that was lined up to take its place, given that the property was aged on the market a few more weeks and prices were going up fast...
In a "Buyer's Market" one of the most critical services a REALTOR® can provide, is his/her ability to "keep the deal together" until closing. Many Sellers believe that once the contract is signed, it is a binding commitment on the Buyers, but this is not always the case.
With many options to choose from, Buyers may keep looking even after a contract has been ratified, and try to use any of the "Get Out Of Jail Free" contingency clauses to get out of the contract, get their Earnest Money back (such as financing, sale of a house, inspections) and buy another house. Often, for less money!
As a listing agent, it is essential that all these contingency "cracks" are "tightened up" to protect the Seller in the event that the Buyers change their mind after the contract is ratified:
The "Contingent on Loan Approval" clause
The "Contingent on Appraisal" clause
The "Contingent on Inspections" clause
Your listing agent must experienced and on top of the game (during negotiations and during the escrow (contract-to-closing) period) to ensure that all deadlines are met, that commitments are followed through and that all parties are performing their tasks in a timely fashion to avoid granting unnecessary "walking away opportunities" to the indecisive Buyers in pursuit of another home.
Of course, it is at best difficult, (and most times impractical) to "force" the Buyers (legally) to perform against their will. But the more meticulous your listing agent is, the better chances you have that the transaction WILL close as planned!