(Another loaded question. Even if unmarried, you have probably developed some ideas on this subject. Again, keep it balanced.)
I think a good marriage is based on mutual respect and trust, with a lot of sharing, communicating, and giving. If you cant express your feelings in a sensitive but candid way, your marriage will undoubtedly suffer.
Learning to communicate effectively with and to understand the needs of another in your personal relationships teaches you how to get along better on the job. And a good marriage frees you to be more successful in your work. All the successful people I've known have had their personal lives in order. So a happy marriage is worth the effort.