If the channels are small, yes is noticeable when the onchain fees are fluctuating also.
Are the "commit_fees" that affect this behavior.
Read more here:
- https://bitcoin.stackexchange.com/questions/89232/why-is-my-spendable-msat-much-lower-than-msatoshi-to-us/89235#89235
- https://old.reddit.com/r/lightningnetwork/comments/cjtbjt/question_regarding_commit_fee/

Look in Thunderhub app, in total liquidity report and you will see where is going

DarthCoin

bitcoin

I was helping a newbie spin up a new LND node (umbrel).

They notice that the LND node balance fluctuates (+/- a thousand sats) from day to day, even when no forwards, no channel closed/open, or transactions have happen.  

They found this concerning as they thought they where losing sats.

I have seen the same thing on my node (same result in thunderhub, RTL, etc..) and I was able to give them some comfort that a similar thing happens to me and they don't need to panic.

Question:
Where should one look to see what is accounting for the fluctuation?  
Anyone have a recommendation for an umbrel App that does a good job in communicating this?