Why Japan discarded captured Russian warships

Why was the Imperial Japanese Navy keen to dispose of captured Imperial Russian ships?

They had become old and troublesome after serving their purpose as a temporary expansion of the Japanese fleet.

Disposal marked the ordinary end of a useful second-hand service life rather than an inexplicable rejection. Captured ships initially helped the Imperial Japanese Navy grow quickly and remained in use while that benefit outweighed their costs. Age, accumulated problems and construction under a different industrial system eventually made them less attractive to maintain. A rapidly modernizing navy can exploit prizes temporarily without treating them as permanent fleet assets.