Anki's default template centers everything. That works well for a single word or a one-line meaning. The problem shows up once an example sentence or explanation runs past two lines: with center alignment, every line starts at a different horizontal position, so after finishing one line your eyes have to hunt for where the next one begins.
A simple rule handles this: center a single line, left-align anything that wraps past two. Left alignment gives every line the same starting point, so your eyes glide down a long passage instead of hunting for it. If there's a numbered list or step-by-step explanation, left alignment is even more comfortable.
You can also mix the two. Keep the whole card centered, but left-align just the example sentence field — the word sits big and centered, and the example sentence underneath reads calmly from the left. It's a combination that shows up a lot in practice.
In ankieditor, click the element you want to change to select it, then pick [Left] / [Center] / [Right] under the Alignment control in Text Style. Click empty space to select the whole card if you want to change alignment at the card level instead.