Shamelessly taken from /u/Aleczandxr's profile on MAL (with some changes more for me to reflect on when rating a show). I also will only rate shows that I finish, with a couple key exceptions.
10/10: Along with obviously everything said down in 9/10 something "clicks" in my brain during or after watching a show that lets me know that it was a 10. By no means is it to say its perfect, but they are for me and will always hold a special place in my heart. (Ex: FMAB because even with its length it never felt like it was fluffing too much and it tied up pretty much every loose end. )
9/10: Absolutely amazing shows that I adore. Great ideas, brilliant execution. One or two elements stopped it from "clicking" for it to become a 10 but anything with this score is likely a favorite of mine. (Ex: Bakemonogatari. I loved it, but it didnt fully click for me. However, it set up a ton of questions about the past and future and made/makes me want to delve into it completely.)
8/10: Great shows that I have very few grievances with. Probably didn't connect with me much or had some debilitating characteristics but still super impressive. I tend to also rate shows im watching this if I feel like its setting itself up to be very enjoyable. (Ex: Erased. You know why. Everything up until then put it close to connecting with me, and then.....)
7/10: Very solid anime that had a notable amount of flaws or things that I didn't like, but in which the parts I enjoyed vastly outweighed the bad. Also goes to great shows that just had 0 connection to me. (Ex: K-On! It just didnt have any real lasting connection to me, but it wasnt bad at all. I couldnt in good faith say it was bad, just not my cup of tea.)
6/10: Usually limited, messy, or disengaging in some way but I still generally enjoyed it. This is the score where the shows are split between stuff I'm glad I watched and stuff I wish I skipped out on. While odd, this is where every show begins off with me unless its a sequel, in which case, it likely starts a little higher as I liked the show enough to watch the next cour or that its degestible enough to me, for me to.
5/10: Basically neutral. Not good, not bad. Usually boring, or held back by a lot of problems. In the majority of cases I wish I hadn't watched it over other shows that are likely much better. (Ex: Hataraku Maou-sama! is a perfect example. It literally leaves 0 impression on me and is merely a "I watched it" to me.)
4/10: Actively bad shows with a lot of elements that I disliked, but with a couple redeeming qualities. (Example: SAO sits here as it began off with a cool premise, but even in S1, it just devolved into typically fluffy crap to me)
3/10: Generally terrible. One or two decent elements or ideas but nothing that comes close to salvaging it. Or maybe it was okay and I just hated the type of narrative it was. (Ex: If Bleach were multiple entries for each arc, quite a few of them would go here.)
2/10: Embarrassing. Morbid Curiosity is the only driving factor to watching it and even then im likely to drop it before finishing. (Ex: SAO2. Decided that since I got through S1, I could do S2. I realised that even a "lets see a train wreck" mentality wore out quick)
1/10: Nothing shows, with literally no value. Typically extremely short nothing affairs that give no entertainment or are pretty much ads in "anime" form. ( Ex: Ragnastrike Angels is literally an Ad for a mobile game IIRC.)