Titration of acid with base or base with acid: can I always use the same indicator?
When phenolphthalein is used as an indicator, NaOH is taken in a burette because then the colour change is from colourless to pink. And this time, it will be easier to observe.

On the other hand, if HCl is taken in a burette, colour change will be from pink to colourless which can't be observed in a single drop.

When NaOH is titrated with HCl using methyl orange as an indicator, HCl is taken in a burette because then the colour at the end point changes from yellow to red which is easier to observe rather than that from red to yellow.