Perfect. Both me and Pat work for software, so that’s why I attended one of his trainings, just to keep the lock clear. The very first question that comes into mind when talking about becoming a tech lead is what is the role of a technical lead?...
The speaker is not (correctly) speaking British or American English and has several inconsistencies with those major Englishes. For example, native speakers don't use trainings as a count noun, and we wouldn't ask someone, in this context "Pat, is there anything more you would like to say to yourself?" but ...about yourself. We also don't work for software, but something like in software.
Anyway, the transcription is not perfect and the speaker is actually saying
... work for ThoughtWorks
Based on the context, he probably means
to clear the air
which in this context would mean
remove any doubts
See definition 2 in the free dictionary
A "lock" (in addition to the lock on your door) is
4 [COUNTABLE] a place on a river or canal with a set of gates which open and close to allow boats in. The water can then be moved to a lower or higher level.
Locks will only work properly if they are kept clear of branches and other possible obstructions.
But if he is using "Keep the lock clear" in this way, it's the first and only time I've heard it. It's not an everyday metaphor, like "clear the air," which is.
Perhaps it's a saying borrowed from his native language, which seems to be German. See his blog.
In addition, a native speaker of English would rarely use such a noticeable gap between the word lock and clear. We would not normally bother to distinctly separate the ending -ck of lock and the beginning k- sound of clear.
Or it's possible the speaker means link instead of lock. (Keep the link clear.)