#More or less useless in vanilla, invaluable in some mods#
More or less useless in vanilla, invaluable in some mods
Due to the way cattle is normally handled in the game, it is almost useless -- it "runs away" from you instead of following you, and, unless your world map speed is insanely high, which is not always the situation, it is very hard not to lose it.
Quests to deliver cattle are hence useless too. If you have a very small army, bandits are likely to try to rob you, and you can neither fight back nor run: you have the cattle. If you have a relatively strong infantry-based army, you will probably just have a hard time moving the cattle. For me, it seemed very annoying and time-consuming compared to other things you may do in the game. With a cavalry-based army, however, you are probably wealthy enough not to engage in cattle-related quests, and moving it with you makes you lose the advantage of speed, keeping the disadvantage of huge price of elite cavalry. Using cattle for sieges with a cavalry-based army is also not needed -- you shouldn't be using a cavalry-based army for sieges at all.
Also, you can't just click "move here" and wait for the computer to calculate the path for you, you have to manually control every single second of movement.
But if you use a mod that makes cattle follow you, and your speed is lower than the speed of the cattle, it may become invaluable sometimes. Why?
- It gives you a lot of food without using space in your inventory. Yes, some mods that allow you full access to the inventory of your companions make it not as valuable, but still.
- It doesn't spoil but allows you to have more variety of food, as raw meat spoils quickly.
It is especially important on sieges. In some mods going on assault is just as dangerous as it is in real life, so you have to take castles by hunger -- or at least you may attempt to. As towns and castles usually have huge reserves of food, they are impossible to take without cattle.
This strategy applies to vanilla, but you just don't need it there, because taking castles and towns by force is extremely easy and fast.