I'm a 23-years-old Q&A engineer who recently started a job in a company who never had Q&A before.
The other day, I was talking with my chief and the chiefs of the development team and told them that I wanted to ask the devs to always write unit test when fixing a bug. This is something that, I believe, is a pretty regular practice and all the chiefs thought it was a good idea.
At the beginning of the daily stand-up meeting, I went ahead and told the dev team:
Maybe you already do it, but it would be good if you write tests for each bug you correct.
The team is composed of several devs (7 I think) and two of them freak out and were absolutely against the idea ("what if...?").
I didn't think this was such a big deal (after all, they are supposed to write unit test when programming, but I don't know if they are really doing it) and I think I'm up against what is called "resistance to change".
So, how could I have present this change in a positive light and such that it wouldn't have raised so much defensiveness?
Note and clarifications
"Write tests for each bug you correct" -> When saying this, I hadn't had time to clarify if I was meaning "every bug fix however trivial" or more of a general rule. So, what I actually meant have no importance here since they had already reacted. (but, if you must know, I wasn't and still isn't decided on that point).
I know they have some unit test and, for having written unit tests before, adding one is usually quick (unless you have to do something you haven't done before but this shouldn't happen that often).
They are suppose to have time to write test in their current workload. If they don't, then Manager is definitively okay to give them more time to do that.
The lead-in I use before the announcement: "Hey, I have an announcement". (So, definitively not a great lead-in).
Someone asked me how this question wasn't a duplicate of my previous one. They are both similar indeed. But my previous answer was more about dealing with one person in a one-on-one situation when this one is more about global change and group interaction. Also, here I don't care about looking nitpicking, I just want people to agree with the changes.
This probably doesn't matter but this is happening in France.