Problems

Readability
Compilation errors in some languages
Mixed Standards

Solutions

Use spaces. Always.
Use automatic tools to prevent tabs in the code.

Context

Developers might see using tabs or spaces for indentation as a matter of personal preference or team convention.

it is generally recommended to be consistent with the chosen method of indentation within a project.

There are a few advantages of using spaces over tabs.

Spaces will always look the same, no matter the text editor, font spacing, or IDE used.

Tabs can vary in width, which can lead to inconsistent indentation when code is viewed on different platforms or in different editors.

Spaces are more consistent in terms of alignment and readability, particularly when it comes to code that involves a mix of spaces and tabs.

Spaces are more predictable and easier to read, which can help to reduce errors in code.

Some screen readers and other assistive technologies may have difficulty reading code that uses tabs for indentation, particularly when tabs are used inconsistently or when tab width is not uniform.

Sample Code

Wrong

def calculate_average(numbers):
    total = 0
    count = 0
        for number in numbers:
    total += number
            count += 1
        average = total / count
    return average

numbers = [1, 2, 3, 4, 5]
print("The average is:", calculate_average(numbers))

Right

def calculate_average(numbers):
    total = 0
    count = 0
    for number in numbers:
        total += number
        count += 1
    average = total / count
    return average

numbers = [1, 2, 3, 4, 5]
print("The average is:", calculate_average(numbers))