Gambling interfaces are engineered to dissolve time: no clocks, fast rounds, results arriving seconds apart. A reality check reinserts the missing information at intervals, displaying elapsed time and net position, and requires an active choice to continue. In Great Britain the feature is required on online slots by the Gambling Commission's remote technical standards, alongside a permanent session clock.
The evidence on such prompts is modest and honest reporting says so: an interruption informs, it does not restrain. Its value is highest at the boundary where a session has quietly run past its intended length, which is precisely the state the interface otherwise conceals.
Why it matters
A reality check is information at the moment it is least available. It cannot stop anyone, but it removes the ability to not know, which is the state in which sessions grow longest.
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