Career in Astrology is not that simple to define. Most of the time when people search on Google for their career prospects in astrology they usually run into articles regarding the 10th house in astrology which shows a person's career, however, the 10th house in astrology only holds 20% of the entire career picture. It's not just about the 10th house, 10th house lord on various houses, or planets aspecting the 10th house. Career through astrology is mainly determine by seeing the person's passion and obsession in life through the main chart, and looking at his or hers divisional chart, yes, divisional chart. In Vedic Astrology there are divisional chart that represents all the sectors of life, so if you want to know about your marriage you will have to surgically open the 7th house and look inside it, that's where the D-9 chart comes into play 'Navmasa Chart'.
In career, VedicAstrologers use D-10 chart, 'Dasmasa Chart', which opens the 10th house surgically and shows the detail about a person's profession. Even D-10 chart is not enough, as I mentioned above that one needs to look at a person's obsession in life, because success in career comes from following one's passion. The signifactor of obsession is Rahu. The placement and sign where Rahu is placed in shows what the person is here to achieve and be obsessive about. Besides Rahu you need to look at all the houses and combinations. Even if a person has Mars in 10th house doesn't mean this person is going to become a police officer, an army general or a doctor; this person could become a writer or actor! What if this person had Venus and Mercury in the 5th house of creativity and Sun in the 3rd house of communication, while Rahu is sitting in the 2nd house of voice and speech? This is why it's very important to look at everything besides one planet, or one house to judge a situation.