Before entering the studio, Metallica collected ideas on "riff tape" recordings of various jam sessions. Hetfield and Ulrich went through the tapes and selected the strongest riffs to assemble into songs. Instruments were recorded separately, with Hetfield playing only rhythm guitar. Rasmussen, with the support of drum roadie Flemming Larsen, taught the basics of timing and beat duration to Ulrich, who had a tendency to increase speed and had little knowledge of rhythm theory. Drums were recorded in an empty warehouse at the back of the studio, which was not soundproof, and caused reverberation. Although four tracks were already arranged, the band members were not used to creating songs in the studio, as they had not done so for Kill 'Em All. "For Whom the Bell Tolls", "Trapped Under Ice" and "Escape" were written from scratch in Copenhagen, and the band put finishing touches on "Fight Fire with Fire", "Ride the Lightning", "Creeping Death", and "The Call of Ktulu", which were already performed live. Lead guitarist Kirk Hammett took the album's name from a passage in Stephen King's novel The Stand. The cover art, displaying an electric chair in the midst of lightning bolts, was conceived before recording began. Metallica initially had sound problems, because its gear was stolen three weeks before the band arrived in Copenhagen. The band members slept in the studio by day as they could not afford a hotel and recorded by night, because the studio was booked by other artists during the daytime. Because the group was looking for a major label deal, several A&R representatives from different labels visited the studio. At first, it seemed that Metallica was going to sign with Bronze Records, but the deal fell through, because Bronze executive Gerry Bron did not appreciate the work done at Sweet Silence Studios, and wanted the US edition to be remixed by engineer Eddie Kramer, and even considered re-recording the album in another studio. Metallica was put off by Bron's failure to share the band's artistic vision and decided to look for another label for the US release, in spite of the fact that Bronze had already advertised Metallica as one of their bands.Metallica had to record quickly because of European shows scheduled 29 days after it entered the studio. Recording finished on March 14, and Megaforce released the album on July 27. Although the original album budget was  $20,000, the final expense was above $30,000. Metallica's European label Music for Nations paid the studio costs because Megaforce owner Jon Zazula could not afford them. Metallica was unhappy with the lack of promotion by Megaforce, and decided to part ways with Zazula. Major label Elektra Records employee Michael Alago noticed Metallica at The Stone gig in San Francisco, and invited Elektra's chairman and the head of promotion to see the August show in New York. The performance at Roseland Ballroom, with Anthrax and Metallica opening for Raven, pleased the Elektra staff, and the band was offered a contract the following morning. On September 12, Metallica signed with Elektra, who re-released the album on November 19. Cliff Burnstein and Peter Mensch of Q Prime were concurrently appointed as the band's new managers. Ride the Lightning was the last Metallica album to feature co-writing contributions from former lead guitarist Dave Mustaine, who received credit on the title track and the instrumental "The Call of Ktulu". The album also represented the first time Hammett was given writing credits.

Question: What is the first name of the person with whom Metallica decided to part ways because they were unhappy with the lack of promotion by Megaforce?
Answer: Jon