system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Some members of US congress have notoriously low attendance ratings and this seems to get brought up a lot before elections (for example, John Kerry in 2004 and currently Ted Cruz). Not trying to exonerate anyone, but what are some possible reasons for a low attendance rate?

Not trying to make a case for anybody. I'm just wondering why. Sorry if this has been asked before-- I couldn't find it if it has.
gpt
Most of the time, everyone knows the result of a vote before it is taken, and it is more of a matter of putting your position on record.  Bills almost never fail to pass because someone didn't show up...in fact, Congress has an informal courtesy system, where if someone wants to be out of town during a vote, they pair up with someone who is going to vote the opposite way, and they both miss the vote.

So low attendance isn't always as bad as it seems.  If you are travelling the country trying to drum up support for a bill, that can be more important than actually voting for it.