Why mines explain many missing submarines

What is the most likely explanation for an unidentified lost Second World War submarine?

Probably a mine, because mines account for many submarine losses that otherwise remain unexplained.

An unidentified lost submarine receives a cautious explanation rather than a firm attribution. A mine is the leading possibility because minefields explain many otherwise unresolved submarine losses during the Second World War. A mine can destroy a boat without witnesses or a surviving report. Absence of evidence should narrow confidence even when one mechanism is historically common.