Question: I was talking to a co-worker about the fact that he ignored certain guidelines when writing his code. He is fairly aware of the established guidelines and a well-defined copy of the same is present on his PC, but he chooses to ignore them and deliver code that doesn't suit the organizational standards.

I wanted to tell him this, "Your ignorance of this matter is unwelcome." 

However, I stopped mid-statement because I realized that this statement would imply that he is not aware of these guidelines. However, he is well-aware of the requirements but ignores them out of choice (probably out of laziness or lack of attention). Is there a better word for this situation? Alternately, how would I phrase this statement in a better way to convey the message that his choice of continuing to ignore guidelines is unwelcome?

Answer: 
The problem is that the words 'ignorance' and 'ignorant' have taken on far stronger meanings than simply 'the ignoring of something'. And that is assuming that they ever did mean simply that. At one level they can mean that someone is 'unlearned', and at its strongest that they are an 'idiot'.

'Ignore' and 'ignorance' can exist on different levels. One can choose to ignore a rule of which one was not ignorant. The fact that I simply choose to ignore an item of junk mail that I receive does not display 'ignorance' on my part (hopefully).

So in the example you mention I think I would either use the gerund 'Ignoring the procedures on your part is unwelcome', or choose another word or phrase altogether, such as 'Your failure to adhere to procedure....'

'Ignorance' like 'illiteracy' is best avoided unless your intention is to offend.
"Ignorance" means that the person who violated standards and policies was unaware of them. Since you report that this is not the case, that the person is definitely aware of the standards and policies, and deliberately fails not to follow them, that word does not apply here. AT best, he is, as Mykolas states, negligent. But what you seem to be describing sounds more like *willful disregard*, or *non-compliance*, or perhaps even *insubordination* to me. 

As for how to phrase the statement of the consequences of failing to adhere to guidelines, I think your question is pretty close to the way to do it, but a bit too gentle, given what you relate in your quesion. If it were me, my dialog would be along the lines of 

> 
> If you continue to ignore (fail to comply, willfully disregard) the standards and procedures for code which you are aware of, the consequences will be dealt with the established policies for dealing with non-compliance, up to, and including termination of employment. 
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