人生无常，大肠包小肠

Meaning

Refers to "stationery addicts" - people who don't love studying but love buying stationery. Often form-over-substance underachievers. There's a saying that "top students just use any pen for notes, while underachievers buy fancy stationery and notebooks." Their studying efficiency doesn't improve, but they try to convince themselves "I bought all this stationery, I'll start studying soon."