The major problem is LED's inability to render colours over the entire colour spectrum.

A lot of suppliers use CRI (colour rendering index) to measure this, and the score is usually 80 or above which is a good score - but it is misleading, because it does not measure rendering for example over reds.

A disadvantage is initial cost for light bulbs. While they are cheaper in then long run, they are more expensive upfront.

Here are some disadvantages:

1. LEDs cannot be used a point source of light for 360 degrees spherical distribution, like the old fashion incandescent light bulbs.

2. LEDs cannot be used for linear sources of light like lasers.

3. High upfront price.

4. Sensitive to current and/or voltage fluctuations.

5. They emit a lot of blue light which can impact moods.

6. They need to ensure that heat is dissipated.

LEDs are dependant on heat being dissipated, so if they are engineered correctly to do this, their lifetime will be greatly diminished.

Incandescent lights were generally warm white, where a lot of LEDs are cool white or daylight white and are installed inappropriately in living rooms, dining rooms etc destroying the atmosphere.

LEDs transmit a lot more blue light than other types of lights, which can cause blue light contamination.

Huge number of cheap LEDs (ie LED lights with low quality drivers) on the market, which will have a high failure rate.

LEDs emit scattered light, so have a small illumination range.

Main disadvantages:

- Upfront cost

- Uneven colours across the spectrum

- Need massive heat sinks to distribute heat