In an effort to win over new viewers, or revitalise existing audiences, new characters join and some are sent to their death in dramas.
In lifestyle programs new presenters can be the impetus for a switch of channels.
Better Homes and Gardens introduces not one but three new presenters for its opening salvo in the ratings war of 2020.
Respected garden expert, author and former presenter on The Garden Gurus Melissa King is one of the newbies.
It could have been quite daunting slotting into such a well-oiled crew, but Kings says regulars Adam Doville, Dr Harry Cooper, Graham Ross, Tara Dennis, Fast Ed Halmagyi, Karen Martini and Pete Colquhoun, and host Johanna Griggs were very welcoming.
"It was quite amazing, we did an all presenter shoot before Christmas when we got to meet everyone," King says.
"I know Graham Ross quite well and he always said it was like a TV family. They were so welcoming of all the new presenters, I was really impressed, it seemed like natural fit."
Doville was the previous newbie and went out of his way to make King feel welcome. "Adam was gorgeous, we both stayed in Sydney and he took me out to dinner. He said just be yourself. He's 'what you see is what you get' and has a vibrant personality. We talked about what's happening for the future [of the show]."
She says all the presenters are very down to earth - pardon the gardening pun - and she has found there isn't the angst in the lifestyle side of the business as their can be in other fields.
"I've worked pretty hard to get to this point. Better Homes and Gardens has been a dream for me. I admire all the presenters. It was a TV ritual in our family growing up. When I was studying [a horticultural degree at University of Melbourne Burnley campus] it was a great inspiration."
King is ready to embrace everything Better Homes & Gardens has to offer. "It's the pinnacle for me. I'm really excited, and ready to go on the journey."
King's focus will be on edible garden projects. "I want to be creative, want to do things people will feel confident to do themselves on the weekends."
With two boys of her own, she is aware of the importance of knowing where your food comes from and reconnecting with nature.
"Having kids of my own, it's fascinating to watch how they interact with the garden. My kids [Noah and Marlon] and I do a lot of potted gardening. They have their own set of tools."
She hopes to do some kids' projects like a pizza garden. "You grow all the ingredients you want on a pizza, then harvest them and throw a pizza party. It's the sort of things that will engage them."
King says there has been a massive increase in the indoor plant market. "Whereas one the indoor plant was an after-thought in design, now they are part of the design. People are using them through the whole house, not just confined to the living room.
"A lot of research has been done to understand the wellbeing and health benefits of having plants indoors - like improving air quality and making us feel happier."
Joining King as new presenters on Better Homes and Gardens are former Bachelor and health and fitness expert Sam Wood, and Weekend Sunrise presenter James Tobin, who will present the latest in tech and motoring.