1. The plaintiff's appeal and the defendant's incidental appeal are all dismissed.

2. Of the costs of lawsuit, the Plaintiff’s appeal.

1. Basic facts

A. The Plaintiff is an insurer who has entered into an automobile insurance contract with C vehicle (hereinafter “Plaintiff”), and the Defendant is an insurer who has entered into an automobile insurance contract with D vehicle (hereinafter “Defendant vehicle”).

B. On February 22, 2018, around 00:10 on February 22, 2018, the occurrence of three traffic accidents occurred. At the point of Busan, the Defendant’s vehicle driven the three-lanes of the five-lanes between the five-lanes, and the accident occurred. As a result, the Defendant’s vehicle moved to the left-hand side and stopped almost right angle in the same direction (hereinafter “the first accident”).

2) After the first accident, the FF vehicle, which followed the same direction as that of the Defendant vehicle, had a part of the rear wheels of the Defendant vehicle, and had an accident to shock the Defendant vehicle on the road while moving to the right side.

(3) After the second accident, the Plaintiff’s vehicle driving behind the same direction as at the time of the lapse of about 38-39 seconds after the second accident occurred (hereinafter “the second accident”). The Plaintiff’s vehicle driving behind the same direction was an accident leading to the rear part of the Defendant’s seat, which was unrhyd in the preceding accident (hereinafter “the third accident”).

4) The summary of the occurrence of a traffic accident is as shown in the annexed Form.

C. The Plaintiff’s vehicle was disposed of by total loss due to the instant third accident, and on May 15, 2018, the Plaintiff finally paid KRW 7,700,000 to the insured of the Plaintiff’s vehicle with total loss.

[Ground of recognition] Facts without dispute, Gap evidence 1 to 5, 11 evidence, Eul evidence 1 (including each number, hereinafter the same), the purport of the whole pleadings

2. Summary of the parties' arguments

A. The third accident of this case alleged by the Plaintiff is an inevitable accident caused by the negligence of the Defendant vehicle that did not take safety measures immediately after the accident, and thus, is entirely responsible for the Defendant vehicle.

(b).