It wasn't always at the end of the season, but there was usually a head-scratching stretch of 3-4 games
2016 seemed to improve towards the end but the schedule got easier as well. BYU did start the season with a three-game losing streak in September.
2017 was a complete disaster all the way around
2018 was up and down throughout the year ending with an almost win vs Utah & a bowl win. BYU lost 4 of 5 games during the middle of the year including home losses to USU & N Illinois.
2019 ended with awful loses to Hawaii & SDSU after seemingly getting things turned around following losses to Toledo & USF. This season was defined by great wins and horrible losses.
2020 just had the one truly awful loss vs Coastal Carolina
2021 ended with a close victory vs Georgia Southern, squeaking by a poor USC team, and quitting versus UAB (comparably not that bad but the team did seem to be trending down).
2022 ended with wins vs Boise, Stanford & SMU after a disastrous middle stretch vs ECU, Liberty, Arkansas & Notre Dame.
2023 ended with the five-game losing streak to miss out on a bowl game again.
2024 has had back-to-back disappointing losses to ASU & Kansas possibly costing BYU a shot at the Big 12 title & Fiesta Bowl.