Times are changing. Social norms have varied in today’s world but that doesn’t mean basic etiquette doesn’t matter. Take Brad Smith, for instance. His company had high hopes for what they thought would be a young mover and shaker. Brad was filled with self-confidence and felt fairly invincible out of the gate. But he forgot that business is really about people and that most of us would rather work with or buy from someone with professional behavior and high standards.

Brad was good about introducing people, but he often substituted a “hello” or nod instead of offering a handshake. When he was busy, he often failed to acknowledge or greet his co-workers unless he needed something from them. His management began to notice and thought it displayed that he was unapproachable and impolite. Their suspicions were backed up when he failed to say “please” or “thank you” for anything.

Brad was an “over-talker.” He was so eager to impress his own opinions that he often interrupted others in midsentence. It’s never easy to not interject, particularly when there is a point to be made. But Brad always pressed on, rudely disrespecting the opinions of others. He often appeared aggressive rather than assertive. In the heat of conversation, he sometimes used derogatory, rude or offensive language. His written communications were filled with slang, which added to the unprofessional impression he began to make on others. Oftentimes he would send emails without subject lines and content full of spelling and grammar errors. Instead of a proper closure, he would sign his emails with a smiley face!

After a few months on the job, Brad got in the habit of walking into someone’s office unannounced. No knock on the door or hello before opening it. Never questioning if it was a good time to talk. He never called or emailed ahead to find a good time to talk. His direct supervisors felt disrespected and often spoke to Brad about calling ahead. But Brad just ignored his boss’ words of warning. Brad also liked to stand over the boss’ shoulder at his desk and read over his shoulder or hang around and listen as his supervisor finished a phone call.

Brad developed a reputation among his co-workers as a gossip who liked to bait others on highly charged topics of politics and religion and then share those discussions to irritate others. He crossed the personal and professional lines on this one.

In meetings, (for which he was frequently late) whether in-house or with clients, he would stop the conversation to take calls, or he would text or check emails. He failed to show genuine interest through eye contact and making an effort to truly listen to others. He was easily distracted and began to lose business. Management began to lose patience and started writing him up because of his behavior.

After three warnings in six months, the company let him go. Is it any wonder that it took them so long?

As you go about your professional career, remember that companies hire for aptitude and work knowledge but fire for behavior. It is something to always keep in mind.

John Daly is the founder and president of The Key Class, the go-to guide for job search success. Click here to learn more about The Key Class, get more information on Thursday night classes in Santa Barbara, or to get his book. Connect with The Key Class on Facebook. Follow John Daly on Twitter: @johndalyjrClick here for previous columns. The opinions expressed are his own.