The phrase "occur less often" is correct and usable in written English.
You can use it when you want to express that something happens with less frequency than normal. Example: With the introduction of new technology, these types of errors occur less often.
They tend to occur less often during pregnancy and with advancing age.
Hot flashes are common in the United States, Australia and Western Europe, but are said to occur less often in Asian women.
The heavy rains damage the fragile Arabica blossoms, and the two-week dry spells that prompt the plant to flower and produce beans occur less often, farmers say.
For boys, such intense emotional conversations, which tend to occur less often, did not contribute to heightened anxiety or depressive moods, according to research by Amanda J. Rose, an assistant professor of psychological sciences at the University of Missouri, Columbia.
Being a chief executive is lonely enough anywhere, but in a market this small and far away from everywhere else, opportunities for shoulder-rubbing and idea-swapping occur less often than they do in North America or Europe.
Clusters such as M62 where the stars are packed very closely together and the rate of close encounters is high have more X-ray binaries than those such as M30 in which close encounters occur less often.
Hospital readmissions and repeat heart attacks also are occurring less often, the study researchers found.
One research paper calculated that an equally wet month probably occurs less often than once a century.
Time-shift occurs less often in Armageddon in Retrospect, and so Vonnegut's gift of nuanced ambiguity is less apparent too.
Preterm premature rupture of membranes also occurred less often in the transabdominal cerclage group than in the transvaginal cerclage group (8% vs 29%, P =.03).
Larger strain amplitudes occurred less often and principal strains fell within the range of −517 (± 118) μɛ to 298 (± 81) μɛ.
