Or lack of documentation/communication within the company.
When key information regarding how you're supposed to do this thing or where that thing is located or how you're supposed to test Y, or how should this particular bit that wasn't communicated in the user story but was talked about in a meeting you weren't at be tackled, or whatever is locked inside people's heads you need to consult with them to get that information out of there.
And yes having information locked inside of senior employees is a bad idea for the company overall, but that's been the case to some extent at pretty much every company I've worked for.
When key information regarding how you're supposed to do this thing or where that thing is located or how you're supposed to test Y, or how should this particular bit that wasn't communicated in the user story but was talked about in a meeting you weren't at be tackled, or whatever is locked inside people's heads you need to consult with them to get that information out of there.
And yes having information locked inside of senior employees is a bad idea for the company overall, but that's been the case to some extent at pretty much every company I've worked for.