Comment by smsm42

I don't know about a year, but usually understanding how things work take time. Understanding why they work this way and not another also takes time. If somebody doesn't take time to learn the background of decisions taken, they are liable to repeat the same mistakes and stumble at the same bumps as have been already passed before and encoded in organization's common lore.

There is something called Chesterton fence principle: https://en.wikipedia.org/wiki/Wikipedia:Chesterton%27s_fence - before proposing to change something, give it an earnest try to figure out why it was like this before, and what changed. Sometimes there's no good reason, or the reason once existing is long gone, and a fresh eye is useful to shake out those cases. In other cases, there are complex and unobvious reasons that cost a significant effort to figure out, and may be not apparent to the fresh eye. So it's better to keep an open and humble mind and at least at first, approach new system with the attitude "please help me learn why it's like this" instead of "this looks wrong, let's throw it away and re-do it from scratch". I'm not sure about a year, but at least a month or two would probably be appropriate. And my experience showed dealing with bugs can actually be very instructive about how things work and why they work this way and not the other.