There are quite a few factors that affect our covert abilities. Some we can alter, some are out of our control. Most of them can however be neutralised or turned from negative to positive if you know what they are and how they work.

Light: Common sense tells us that the level of light in a room affects our covert abilities. The lightlevels outside shift depending on the hour of day. Lightlevels of shops stay pretty much static, as do most rooms indoors. Pay attention to lightsources such as yellow stone rings, torches etc. If you want to move and act in stealth, make sure you are not lit up like a Hogswatch-tree if you can help it.

Temperature: If you want to hide and sneak successfully, you will learn to keep track of your temperature. Day and night, seasons and regions all have different temperatures. If you dress wrong you risk getting too hot or too cold. When this happends you will sweat or shiver, something that will bring you out of hiding. Trust me, this happends at the worst of times.

Burden: Beeing burduned will somewhat hamper your dexterity. And since dexterity is what we use the most for our covert abilities, this will lower our skills. How much you can carry without beeing burduned is dependant on your strength. When you do things that might alter your strenght, make sure to check if this has made you burduned before trying anything covert.

Security: This refers to shops, who have a base security level, their "perception" so to speak. The base level of shops are individual. In addition, the level of security is raised for every steal made in this shop. This means that a shop which is often targetted by thieves will eventually have a very high security level. This level reverts back to base security after a while, so it is not a permanent raise.

Weight: The weight of an object is a factor in how difficult it is to steal. The heavier, the harder.

Price: The price of an object in a shop affects how difficult it is to steal. The price of an object carried by an npc should not have any bearing on the difficulty af a steal however.

Position: An object held or worn is naturally more difficult to steal than an item which is carried.

Hiding: Hiding will affect your success in stealing positively. Both from npc and shops.

Stats: There are ways to alter your stats, both positively and negatively. Naturally this will affect your skills accordingly, and thereby your success. There are a number of stat-items in the game, mostly found through quests or bought for a high price from various shops.

Perception: The perception of an npc will be tested against your abilities when you attempt to steal from them or use a suprise attack. When using snatch, other skills come into play for the victims defence.

NOTE: Just because some things affects your skills negatively does not mean it has to be a bad thing. Doing something close to the edge of your ability can actually increase your skills by the way of taskmasters. A good thief learns how to use the above factors to get close to his or her breaking point.