Accepted answer
10 days is about 8 working days once the weekends come out, and a customs queue runs on working days. The restatement matters: 10 days of silence feels like a decision, and 8 working days is usually a queue. Past 8 working days the distribution shifts. Routine clearance rarely runs this long, so the live candidates are a document query that never reached you, a valuation question, or a hold pending a decision you will be told about in writing. The tracking page is not the record. The record is the notice, and a notice arrives on paper or in a portal, not as a status change. Ask the carrier for the entry number and whether a query has been raised against it, in those words — "where is my parcel" gets the tracking page read back to you. And write the 10 days down somewhere durable now: if this becomes a dispute, the timeline is the thing you will be asked for and the thing nobody kept.
The short version: most holds are documentation queries, most resolve, and the paperwork description is the variable that predicts them.
Most holds are documentation queries: an incomplete description, a missing value, an unclear commodity code. They generate a request for information and resolve when it is supplied.
On the detail: duty and import tax thresholds vary by country and by value, and are separate from any question of whether the goods are permitted. Paying a charge is not an admission of anything.
Customs classification is driven by the commodity description and code on the declaration, which is why the description predicts treatment.
The caveat is that nothing here is legal advice and jurisdictions differ more than any general statement can capture.
Keep every document. It is the only record that will exist.