The raw table has five rows, but Tuesday has NA for orders. For this first pass, the rule is simple: drop the missing row and do not fill in a guess.
After the drop, the plot has four dots. The summary table names the effect: five raw rows become four clean rows, one row is dropped, and the mean of the kept values is 6.
A tiny cleaning readout: make one missing-value decision, then show how the clean rows and plot differ from the raw load.
highlighted = computed this step
Load before cleaning
Start with 5 pinned rows; only 4 rows have numeric orders.
raw rows before cleaning
Choose the cleaning rule
Drop the 1 missing row; do not invent a replacement value.
drop missing row
Show the clean plot
The clean plot has 4 dots: Mon 6, Wed 9, Thu 3, Fri 6.
clean plot after dropping missing
State the effect
Cleaning changes the readout from 5 raw rows to 4 clean rows, with mean 6 over kept values.