If housings are new, check under the ferrules to see if the ends are square. If not, make them square. Often they're too long and you can get nicer bends by shortening them. Then just squirt them clean with some spray and maybe follow with a bit of light oil. Ensure cables are undamaged.

If the housing isn't new and the cables look okay, worn liners in the housing are the likely culprit. Along with excess length being common...