Word Choice is Important - it fascinates me that irregular, intermittent, infrequent, periodic, erratic, patchy and random all have the same denotation but very different connotation. One has to sense the difference. The dictionary is of no help! I remember doing a class exercise...

I am firm; you are obstinate; he is pig-headed.
I am concerned; you are curious; he is nosy.
I am thrifty; you are a bit tight; he's cheap.
I day-dream; you are an escapist; she ought to seek help.