Usually, an earn out clause is preferred by the buyer; however, there are some advantages to both parties in a transaction:
The advantages for the buyer
The buyer can retain the expertise of the seller(s) in the company after buying the business. In addition, the buyer will also be able to defer part of the purchase price to a date in the future.
An earn-out provision also encourages the seller to remain in the business following completion and attempt to make the business a success.
The disadvantages for the buyer
The parties may have conflicting interests, as the seller(s) will want to maximise the purchase price, whereas the buyer may want to keep the purchase price at a lower level.
The seller(s) will also want to ensure that the buyer does not do anything that restricts the business's growth and thus restricts their ability to hit the earn out targets, which can lead to a difficult relationship between the parties.
The advantages for the seller
Depending on the terms of the earn out, it allows a seller to benefit from a positive development of the company, as an earn out will usually be contingent on the positive performance of the company.
The earn out could also allow the seller to benefit from synergies in the buyer's group, potentially leading to the seller maximising returns.
The disadvantages for the seller
An earn-out clause will bring uncertainty to a seller as a portion of the purchase price will be subject to the company achieving a certain objective/target.
It may also be the case that a particular market suffers from outside factors outside of the seller's control (e.g. the covid-19 outbreak).