Why did Bonanza end in the middle 14th season?

"Bonanza" ended during its 14th season primarily due to declining ratings and changes in the television landscape. The show, which had been a staple of NBC's programming since 1959, faced increased competition from other popular series and shifts in viewer preferences. Additionally, the passing of key cast member Dan Blocker in 1972 significantly impacted the show's dynamic and audience appeal. Ultimately, these factors led NBC to cancel the series in 1973.