After successfully opening Line 14 as a fully automatic line, the RATP began to explore the possibility of automating existing lines on the system. The agency first focused on Line 1, since it is the busiest of all of the Paris subway lines, and also the line most frequented by tourists. Automation not only allowed Paris to remain as a model for technological innovations in the railway industry but also increases the number of lines in normal service when RATP workers are striking "(from MP 05)". This was shown when the transport union engaged in industrial action in September 2019 without affecting service on Line 1.