1. Revocation of the first instance judgment.

2. All plaintiffs' claims are dismissed.

3. The plaintiffs' total costs of litigation.

1. Facts of recognition;

A. Plaintiff A, a personal entrepreneur conducting construction business, etc. with the trade name of “E,” was awarded a contract for construction work for a factory located in “D” in “D, and was awarded a subcontract for the said construction work amounting to KRW 29.7 million for the construction work cost, around May 31, 2017. Plaintiff A, a wife of Plaintiff A, jointly and severally guaranteed the Defendant’s obligation to pay the said construction cost, while jointly operating the said E.

B. On March 28, 2018, the Defendant filed a lawsuit against the Plaintiffs on March 28, 2018, seeking the payment of the construction cost of KRW 14.8 million with the Suwon District Court Decision 2018Da1505, Suwon-si, the Ansan-si Court. The said court “the payment of the amount of KRW 14.8 million and the amount of money calculated at the rate of 6% per annum from August 27, 2017 to the date of delivery of a copy of the complaint, and 15% per annum from the next day to the date of full payment” is “the execution recommendation decision of this case.”

The decision on performance recommendation was made on May 3, 2018. [The fact that there is no dispute over the grounds for recognition, the purport of all pleadings, and the purport of the whole pleadings.]

2. The parties' assertion

A. Although the Plaintiffs paid KRW 16.5 million to the Defendant of the instant contract price, the Defendant did not proceed with construction work equivalent to the paid contract price, and thus, there is no further payment for the Defendant. Accordingly, the Defendant asserts that compulsory execution based on the decision on performance recommendation of this case should be denied.

B. The defendant asserts that the defendant is liable to pay the remaining construction cost according to the payment rejection written by the plaintiffs.

3. Determination

A. In full view of the purport of the argument in the evidence No. 1 of this case, the Defendant: (a) was awarded a subcontract for the steel frame construction of this case in the amount of KRW 29.7 million from the Plaintiffs; (b) reduced the construction cost by KRW 20.7 million following the adjustment, etc. of a part of the construction; and (c) while performing the construction, the Defendant was performing the construction.