When a good Software Developer is called out on an actual mistake or subpar performance, they immediately say "Thank you for your feedback!", they own up to their error by apologizing, they do some introspection to understand how they failed and empathetically become aware of the impact their mistake/subpar-performance had on their customers and team, they genuinely ask for help if needed to understand how they could do better, and they resolve to improve.
When a bad Software Developer is called out on an actual mistake or subpar performance, they immediately get angry and defensive while seeing feedback providers as the "enemy", they avoid owning up to their error by making lame excuses and lying about the situation, they express apathy towards understanding how they failed, selfish lack of empathy, and lack of interest in becoming aware of the impact of their mistake/subpar-performance on their customers and team, they think they are above the need for help, and they do not put any effort into improving.
Remember that giving people honest unfiltered feedback after they made a mistake is the nicest most loving thing one could do for them as it helps them become aware of whether they need to improve or they are on the right track. Feedback has the positive intention of helping someone improve regardless of whether it is negative or not. When people discourage honest feedback or want filtering of it (like adding an emotionally insincere "positive" tone), they end up stagnating in mediocrity and never improving because they never get the full impact of their mistakes on their customers and team.
I never trust anyone who doesn't immediately say the equivalent of "thank you" and shows genuine concern when receiving feedback, whether harsh or not. In fact, that is the biggest difference maker between top performers and average performers is that top performers will accept any sincere feedback no matter how harsh it might be, so they end up improving many times over average performers. That is also the difference between how mature adults and children handle feedback. Children cannot accept any feedback, which is why parents 'baby-talk' them. On the other hand, mature adults can accept the truth in any way, shape, or tone. If someone needs 'baby-talk' privilege, they are not qualified adult hires in the first place.
In summary, everyone makes mistakes; nobody is perfect. And, the nicest most loving thing to do when people make mistakes is to provide them with honest unfiltered feedback to help them improve. But, the difference between good Software Developers and bad Software Developers is that good ones own up to their errors and correct them whereas bad ones do not own up to their errors and never correct them.