If we look at things from the plant's perspective, no matter how bad a leaf looks, if it's creating more food/energy than it's using it is a benefactor to the plant. Too, the plant has chemical messengers that keep it well informed with regard to whether or not the leaf is pulling it's weight. If it isn't the plant starts the shedding process, the first phase of which is resorption during which the plant reclaims/ recycles nutrients and other biocompounds from the leaf to use elsewhere within the plant; so, even if the plant has "decided" the leaf's gotta go, it's programmed to be economical about the process and takes what's available from damaged leaves before they're shed. Removing leaves because they're damaged or unsightly denies the plant that ability.
From your perspective, it might be that you just cannot tolerate the appearance of the spoiled foliage. Ultimately, you're the boss, but it's good to understand what the trade-offs are. Judging by the way the plant looks, it's not as serious as life or death, but it would be a minor negative. Plants are genetically programmed to be shedding organisms and they shed to reduce their mass as a way of coping with resource shortfalls, so when it comes to shedding parts, the plant knows best.
Al
