The Walking Dead originally had a very different plan for Daryl (Norman Reedus), but it wouldn't have worked out well for the AMC series. Daryl, who was introduced in only the third episode, is one of the last two remaining season 1 characters, the other being Carol (Melissa McBride). After outlasting everyone else, Norman Reedus now has top-billing in the show, which is nearing its 11th season and its 10th anniversary.
For most of the show, Daryl was Rick's right-hand man, his most trusted ally, and his "brother", but things haven't always been that way. When Daryl first appeared on the show, he wasn't interested in making friends with Rick and his family. Daryl was intent on finding his brother, Merle (Michael Rooker), and furiously blamed Rick's people for his disappearance. Though the group's relationship with Daryl certainly got off to a rather rocky start, Daryl remained with Rick and the others and used his skills as a hunter and tracker to contribute a great deal to the group.
From there, Daryl evolved into a fan-favorite, but early scripts for The Walking Dead would have sent Daryl in a completely different direction. According to Norman Reedus, the original Daryl had a "chip on his shoulder", used drugs, and was a bit of a racist (via CinemaBlend). While Daryl exhibited some of these characteristics in season 1, he ended up becoming someone else entirely. Reedus even says that he had to fight to change this plan - and thankfully he did. Reedus didn't want Daryl to be a "full-blown Alcoholics Anonymous member"; instead, he wanted Daryl to be a character who could grow into "somebody you respect". Reedus says that now Daryl is "super direct" and "honest".
The Walking Dead season 1 did have a moment where Daryl referred to Glenn (Steven Yeun) as a "Chinaman", unaware that the character is actually Korean, but though Daryl may have been slightly offensive and difficult get along with in his earliest episodes, he wasn't a racist or a drug addict. If The Walking Dead had moved forward with this plan, it's hard to imagine Daryl ever gaining the popularity that he has today.
First of all, the early version of Daryl sounds a lot like a replacement for Merle, whose antagonistic behavior made him someone who constantly clashed with the other characters. It would seem that Daryl would have served as a foil character whose main purpose to was to cause friction and conflict. If this is what they had done with Daryl, it's unlikely that he would have become a fan-favorite. If he was presented as a character who fans couldn't care about or believe that he could be redeemed, eventually The Walking Dead would have moved on from him and killed him off. Fortunately, The Walking Dead opted not to take this path, and instead gave fans what became of the show's most beloved characters.