I'm a Translator/Interpreter residing in Brazil. I believe I’m above the average in terms of skill and competence, because I see a lot of badly translated works in movies, TV shows comic books and video games. (Famous ones, actually)
A translator doesn't just convert a text from one language to another. A translator is also a text editor. Anyone can use softwares to translate texts, but those would be literal translations. A true translator analyzes the text, its meaning and its context in order to transcribe it to the target language and target audiences.
Translating for dubbing requires that the translator adapt the translated text to the movement of the character's lips on the screen. Sometimes, though, a translator will be asked to localize the translation, which means he or she will have to adapt the content to a "local" audience. Good examples of localized dubbing are animes that originally had "inappropriate" content for most audiences but were edited so that they could release it on American children's TVs.
Translating for subtitling doesn't require all those adaptations, but the translator must still make sure the subtitles are properly timed so that they are easily readable, and in time.
A video game is software and should be translated as one, but with a few differences. Nowadays, games are not just menus and help files. In game characters are played by voice actors (this means they must be dubbed into the local language of a foreign market) and those speeches have subtitles too. In high-end games you don't have to worry about synchronizing your translation to the character's lips. The games’ programmers will usually synchronize the lips' movements to the actors' speeches. (An example of a translated video game is the Brazilian edition of Starcraft II: Wings of Liberty, even though it has a number of translations mistakes and misinterpreted jargons)