Bug report: duolingo doesn't mark (small) mistakes
For quite a while I had this feeling that duolingo says "all correct" while my answer wasn't fully correct, but had some minor typoes.
But I wasn't able to catch it, until today.
See the attached screen shot: I had 2 typoes but duolingo marked only one with red.
I'm quite sure this also happens when there is 1 typo, and then Duolingo doesn't mark anything in red...
Hey there, like FrankySka says, that's not an isolated bug - it's intentional actually. :) The idea behind this is the following: in your example above, you had a regular old typo, "Reic", and you used two "s"es instead of the ß character. The latter, as you can see from the message ("Pay attention to..."), is known to the grading system as a specific type of mistake, while "Reic" is not - we just think it's a typo.
Our logic is that since we can only teach so much in one sentence, we want to point out only one type of mistake. So instead of telling you "Hey, don't worry too much about it, but using "ss" for "ß" is not proper spelling! Also, there's a typo there. And another one! And also don't forget to capitalize nouns!" (dramatization), we look at the different types of mistakes you made, and we pick the one that we think is worth pointing out the most. In this case, the "ß" character one. Or if you get an article wrong and the verb conjugation is off, we'll point out the verb conjugation because that's a more serious mistake. However, if you have more than one mistake of the same type (getting two articles wrong, or simply using a wrong word more than once, like this https://www.dropbox.com/s/2jvaof327qc8jlv/Screen%20Shot%202013-11-24%20at%2002.15.43%20AM.png), we will point out every one of them. If not, be sure to send another bug report! :)
This not-making-all-mistakes-red thing does happen in all the other languages (well at least spanish and french) as well. I'd would be nice if all typos/potential actual mistakes would at least be marked red. I don't think they have to count towards lowing hearts necessarily. I have a tendency to very consistently spell words incorrectly and never knowing that I do, and this would help! :)