In my main comic, the characters wear the same outfits. There's every day wear, pyjamas and outfits for swimming. That's about it.
Me too, i try to keep the silhouettes similar and especially the shape language. If i can't fudge the silhouettes, like for example in my second chapter and in my upcoming fourth chapter, then I tend to fall back on clothing choice, specifically collar choice. A character's choice in clothing is a greater personality indicator.
New here to TAPAS so I was like, hey I love this style so much just from this one pic. Lemme find and follow this artist com- ah- 
That aside... you have a fantastic style there. 
@TheDWrek83 omg hehehe, thank you so much, it's really nice to hear 
@IndigoShirtProd I absolutely agree! I especially like to throw some characters in very uncomfortable situations and indicate this not only with the overall plot, but I really enjoy absolutely changing their clothes to something very unusual (thus uncomfortable) for them 
I'm mostly have my characters wear the same thing,
sounds lazy, I know, but it does work for most cartoons, and it can allow for some funny self aware jokes,
It's funny and for the times we're living in, it doesn't surprise me. It actually fits because I am sure I'm not the only one during this pandemic that hasn't changed their outfit in a few days...a week maybe... xD And to be completely honest, I have multiples of types of articles of clothing. I will have the same shirt in different colors, a copy (or copies) of one kind of shirt or pants, etc because I have issues with just having one. Like first of all, I love even numbers, secondly, I like having backups so it's not unusual for me in the slightest to have the same outfits. SO, as a reader this makes me feel normal when characters do this xD
I vary them because they change clothes. But they tend to be in clothing that suits what they're doing.
The characters in Errant will change outfits, since it just feels right for the level of realism and modern setting of their world.
It'll also be used as a sort of storytelling aid, because what they choose to wear will tell you a lot about where they're at. In this current part of the story, we have Rekki in this ridiculous, bombastic kinda outfit that represents somebody trying to show the world she's a powerful hero with enough confidence to pull off chest-high-red-flared-sailor-pants and a cropped bomber jacket, and we have Subo in clothes definitely more suited to lounging around in than fighting. They'll be wearing different stuff when we get to 'tomorrow' in this story!
I do change up the looks with an eye to keep each character's "style" intact though. So like... Rekki always wears kinda warm and hot colours and her clothes always have a sort of tomboy/ladette/member of the spice girls feel. Like she's a bit sporty, a little bit britpop retro etc. Subo will always look like somebody you'd meet at an organic food market and wears all these earthy, natural colours and greens.
For me, I like changing up the colors of my character's clothing or the logos, whatever it is, but I maintain like 4-5 variants of a clothing design. Long sleeve tunic with pants, plain t-shirt with shorts or pants, a button up shirt with pants, tank top with shorts, and perhaps a sweater with pants. V-neck shirts and plain t-shirts are very abundant xD I want to make more kinds of outfits, though. When my characters go out, I try to vary their outfits more. I am probably gonna make a lot more sketches of outfits in my sketchbook since this thread has inspired me. But I don't find characters who don't change their outfit as strange. I don't mind it, personally. It is easier for the creator, which I can guarantee sometimes we do take part in the easier routes, which I can never be mad at or blame a creator for. The professionals have done it (example: characters who have only 4 fingers because it saves time) and it isn't illegal xD I find it funny when as @WhoDrew mentions, the characters are even self-aware of it.
Instead of drawing them in the same outfit all the time, I tend to prescribe a "style" to them, trying to maintain their color pallet, silhouette, and shapes. Like my main character tends to wear leggings and loose t-shirts, and I tend to keep her color pallet to yellow, white, and gray. I also try to incorporate some kind of heart shape somewhere on all of her outfits. Hopefully, this method lets her design still be recognizable while still feeling more "realistic"
Here's some examples of her same-but-different outfits:
). 
I will vary the outfits based on more casual or formal settings. I try to keep the colors similar though because I have my characters color coded including their speech bubbles so that they stick out in my reader’s memories. That way when they see the character who wears a blue shirt and has blue speech bubbles it’s obvious who the character is and who is saying what. This is a trick I took from BL comic creator Sakurada Yana.
In Aoihito I vary character's outfit. They have their iconic piece of clothing, but they wear different stuff. On one hand this is good, because I don't have to draw them in the same outfit all the time if it annoys me, but on the other hand I have to come up with new outfits ideas. 
In TMoN characters are in a situation where they cannot really change their clothes. I made their clothing layered, so they can take one piece off when they need it. So far it made me realize I'm never making a character that wears long coat ever again. xD
I mostly draw them in their same outfits, but in the latest part they go to another world with a different ecosystem and they have to use special suits, so the costume change was part of the plot.
For the most part mine wear the same outfits (a couple of the MCs wears in layers so there are slight changes at points), but only because realistically thats the only clothes they own in their current situation.
However there will be points in the story where their outfits start changing a bit as a form of character development.
I also find it fun to see them in different outfits so yeah loool
My characters have default outfits that they wear 90% of the story, but sometimes I might have them wear something different. I mostly keep things the same since it's easier for myself and the readers.
For one of my chapters, the lead had to wear a different outfit because she fell asleep in her usual day clothes and it'd be weird for her to wear them to school the next day or have multiple copies of the same outfit.