Cooking times will vary depending on the type of meat that you are cooking. Initially meat should be browned before going through the full cooking or roasting process to seal in the juices and it is this browning that provides the flavour. If it is a roast then turning the oven up high for the first twenty minutes of the cooking period will provide this browning. Should it be a smaller piece of meat, perhaps diced beef that is going to be added to a casserole, then it can be browned by frying it before it goes into the oven. As the outside of meat will usually have some form of fat covering it is this fat that provides additional flavour.
Slower cooking times are preferable for the vast majority of meat as it gives time for the juices to bubble away inside the meat and tenderise the fibres. Because some meat has less fat and therefore fewer juices then these types of meat, such as venison, will benefit from basting or larding during the cooking process. This will lead to a more succulent and tastier meat.
If you are going to be roasting a joint of meat you can run the risk of the meat sitting in its own juices in the roasting tin while it is cooking. This is not necessarily a good idea as you want to roast the meat and not poach it; the point of roasting it is the flavour that it provides. If you put the joint on top of something this will keep it at a level above the liquid, this could be a metal rack or, if roasting for example a chicken, some vegetables, and these vegetables will then roast along with the meat and provide a good base for the gravy. Overall cooking times can therefore be reduced as you are cooking the vegetables at the same time as the meat instead of needing to undertake it separately.
Cooking times for meat need to be adjusted accordingly depending on the type of meat being cooked. For example, poultry such as chicken will need to be cooked all of the way through in order to kill all of the bacteria present. Other meats such as beef can be cooked to your liking as some people prefer it to be served rare, so cooking times will be a lot less in this instance.
In any of these cases giving the meat an initial high temperature for the first twenty minutes is a good rule of thumb. If you have stuffed the meat then the cooking times will be longer, usually adding an extra thirty minutes to make sure the meat is cooked through.
Incorporate into your cooking times the time needed for the meat to rest after it has finished cooking.