Why would mrs bennet choose to " secure" a husband instead of growing to be an old maid ?

Mrs. Bennett lives at a time when women had no other choice but to be married if they intend to live a decent life. Any husband would be better than no husband; being an old maid was such an embarrassing situation to find oneself in. Mrs. Bennett has been somewhat lucky because even though she is of low station, she has married "up." She hopes that her daughters can also marry up.