Because QuickC's inline assembler doesn't require separate assembly and link steps, it is more convenient than a separate assembler. Inline assembly code can use any C variable or function name that is visible (in scope), so it is easy to integrate it with your program's C code. And because the assembly code can be mixed inline with C statements, it can do tasks that are cumbersome or impossible in C alone.
The uses of inline assembly include
Writing the body of a function in assembly language
Spot-optimizing speed-critical sections of code
Calling DOS and BIOS routines with the INT instruction
Creating TSR (terminate-and-stay-resident) code or handler routines that require knowledge of processor states
Inline assembly is a special-purpose tool. If you plan to transport an application, you'll probably want to place machine-specific code in a separate module. And because the inline assembler doesn't support all MASM directives, you may find it more convenient to use MASM for such modules.