The seals it has for the pitcher, especially the one at the base, comes into contact with the liquids and leaves a rubbery taste. This becomes particularly noticeable when you go to drink the water at the end, i.e., when the pitcher has been emptied of the food it contained and you pour a little clean water to rinse it out and then go to drink that water. For the taste to come out in the water means it also comes out in the liquid foods you had inside before. Simply, this is not noticeable at first since this rubbery taste is obviously masked by the stronger flavors. I tried various methods to make these seals not impart a taste, such as soaking them in hot water for a while, thorough washing, etc., but I saw no results. The rubber still has the same smell and imparts flavor (since it is not odorless, it means that its molecules are released into the air and are perceived by our sense of smell, especially when they come into contact with liquids processed by the blender...).

Update 29/7/2024: The motor smoked, rest in peace.
I might go for a more durable one of 1400 watts and above with the same capacity of 1.5 liters. This one, at 800 watts, didn't last long. I didn't use it much since I was working with an older one I had, because that one didn't have its seal exposed to food and didn't impart a rubbery taste to the water at the end like this one here. Now let's see if we can find a good one in heavy-duty watts from now on.
Update 30/7/2024: It’s still alive after all. It just had a bit of a meltdown with the frozen bananas, which is why it smoked. Today it was working normally although I still saw a little smoke at the end (where the pitcher sits right after I took it out) since I again put in fewer frozen bananas than yesterday. I ordered a professional blender of 1800 watts with a glass pitcher of 1.8 liters for 85 euros (89.90 euros with shipping costs from Speedex).
September 11, 2024 update: It is the IZZY IZ-6500 Limited Edition (223916) Blender.
After 1 month of use (almost every day), since I figured out how much liquid it needs inside to work perfectly, I give it 5 stars. There is still a little plastic material that comes into contact with the food (from seals inside the pitcher), but it is so little that it doesn't leave its taste in the water like the cheap blender. The seal must also be made of silicone and doesn't smell like that of the cheap one. However, a slight taste and smell of the seal can be detected if you are a dog like me lol.