TV shows don't always go to plan. Sometimes low-ratings will mean the network pulls the plug, others the lead actor walks away, necessitating a complete rejig of the series.
But where TV has the advantage is the ability to adapt almost on the fly. Most U.S. network shows, for example, can flip things around mid-season if something isn't working, or at the very least use the summer break to change things up, which can lead to plans being altered.
Other times it might be the conception stage, with various plans being tossed around before the idea that will then make it to air is settled upon. Pitches are made, altered, scrapped, and whatever the reason, there are a number of beloved, celebrated TV shows that came close to being very different at various points of their run.
Only Fools and Horses ran for seven series from 1981-1991, before returning for a number of special trilogies that would eventually end with 2003's Sleepless in Peckham, becoming one of the most iconic British sitcoms in the process.
However, at one point it looked like the series was going to have to wrap-up in Series 5, after David Jason announced his intention to leave the show. The episode Who Wants To Be A Millionaire was going to be the finale, which would see Del Boy heading off to Australia, with creator John Sullivan planning a spin-off centred around Rodney, titled Hot-Rod.
Luckily, Jason had a change of heart and the series continued, but if he hadn't then we never would've had Del falling through the bar, the Jolly Boys' Outing, or the Trotters dressed as Batman and Robin.