Screening is the operational core of sanctions compliance and it is a string-matching problem before it is anything else. Lists carry names in multiple transliterations; customers supply names with spelling variants, honorifics and word order differences.
Systems therefore use fuzzy matching with tunable thresholds, and the tuning is a genuine trade-off: too loose and the alerts are unworkable, too tight and a transliteration variant passes. Enforcement actions turning on a missed match usually turn on that setting.