Q: What features are essential for a video game to be used for training and why? A: A very interesting question. The answer is "it depends". I depends on what type of training the game will be used for and what budget and/or time constraints are present.
In reality this means the defining factor/s is/are not so much about the 'looks' of a game, how shiny or detailed the worlds are, but rather more often a question as to
how easy it is to modify and/or change existing games or engine technologies to meet the required needs of a given training project. For example...
Example 1: A security firm wants to train personal to deal with terrorist threats at various types of facilities. It has a reasonable budget, but time is critical because local Government agencies need to deploy these personal to further train local agents.
Possible Solution: Games based around tactical First Person Shooters, the recent Call of Duty for example, has game play mechanics that contextually fit the requirements of the security firm.
Example 2: Similarly, a medical trust wants to research better practices within the surgery environment. Budget is reasonable and time is not critical.
Possible Solution: Again an FPS might be suitable, perhaps one with less 'aggressive' movement and/or tactical requirements. Half Life 2 might be considered appropriate in such situations because the general mechanic relies more on character interaction than it does outright 'action'.
Example 3: A university wants to test a number of psychological ideas and principle on groups and crowds safely. Budget is reasonable but not great and time is not of such importance.
Possible Solution: Social media, 3D chat and/or virtual worlds in particular, might prove the better option because by default the general mechanics operate within a context that's similar to the requirements of the project.
At the end of the day to answer the question properly, the mechanics of the training exercise would need to be defined and nailed down. Once those criteria are in place, more precise and appropriate questions can then be asked in terms of how that relates to overall costs (short and long term) and the availability of time and resources to accomplish the desired outcome; baring in mind that it takes game development studios with dozens and dozens of employees a good number of years and several million dollars to do what they do.
Define the need, then find the match.
