B2 visa experience share

My parents got visa couple days ago in Shanghai first time. If my father does not come here this time(only my mother come here), will it affect my father's later visa application? If there is any same case, please share.

I believe US consulate are applying more strict rules in recent years and there is almost no exemption for some rules such as extension means no automatic visa obtaining at later time.

Some experience on B2
1) Only my materials were used in getting visa. All chinese materials were returned from window when they were going to submit. Visa is M entries, no Annotation, 6M expiration.
2) Answer questions honestly and naturally
3) Material prepared: cover letter to consulator, copies of status (passport, H1B with I-94, SSN), bank statement (official for immigrant, spent $25), salary check, degree certificate obtained from USA
4) Lucky is number 1. The success rate is about 10% on that particular day (not necessary all are B2)

Experience from others ( more than 3 cases)
1) Never extend I-94 time, never stay longer than the time stamp in Annotation if there is. Otherwise, you will have trouble in getting visa letter. Of course, you do not need care if they will stay foever or no come back.