Matte finishes kinda suck. They will actually get stains more like fabric than painted finishes. One of my bikes has a frame with a black and white matte finish. There are spots of mud on the white (probably the black too) - red clay - that won't come off. I've used several cleaners... still there.
Plain old grease is a problem too - you have be very careful how you clean/wipe the bike. Example: that little bit of crud that forms at the headtube-fork... that must be wiped side to side - not up or down. If the grime is smeared onto the headtube or fork... it takes a few minutes with a degreaser to get the smudges off. So, you can imagine the chainstays.
If you do get a matte finish, look into coating the frame with a paint sealant. I did this with my newer Scott Foil and it makes clean up much easier.
I used an automotive coating - CQuartz on the Foil. It made a very small change to the sheen - like maybe 5% more gloss. But, grease and bugs, etc. wipe off much easier.
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