System of Sounds

Every language has a system of sounds in its pronunciation.

Everything works via the relationship of contrast.

If there is not enough contrast between two things to easily, quickly & reliably distinguish them, then their relationship does not have enough contrast.

The concept of contrast is in every layer and aspect of language, and the contrasts within each aspect interact with contrasts in other aspects.

Do your very best to abide by the contrast system of whichever language you are learning! You might think that your personal way is "good enough", but if your contrast methods do not match those of the people you are talking to, they are likely to misunderstand you in ways that you can't even imagine.