Rack up
Definition 1 of 2

Negative Undertone
The phrase often implies negative connotations when discussing gaining debts or problems.

Be careful not to rack up too many parking tickets.
Gradual Process
'Rack up' indicates a gradual increase, not immediate.

She gradually racked up enough savings to buy a car.
Casual Expression
Used in everyday conversation, but might be too informal for very formal contexts.

Over time, I've racked up a nice collection of vinyl records.
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