what on earth did you do to illicit that accusation?

Send them along the wrong course? Barge their boat? Move the mark right as that particular boat was approaching (and move it back)? Cause it to rain? Snuck onboard and opened their seacocks overnight? Failed to pick them up after their boat sank?

Jeeze... even those (well, maybe the last two) wouldn't "ruin the entire day/weekend" but that's just me.