完 does not say finished. It says you can see the bottom

Where the picture shows up in 完

1. 1

   the pages run out

   我看完这一章就睡。

   wǒ kàn wán zhè yì zhāng jiù shuì

   I'll read to the end of this chapter and go to bed.

2. 2

   the money runs out

   卡里的钱花完了。

   kǎ li de qián huā wán le

   The money on the card is gone.

3. 3

   the meeting runs out

   会开完了吗？我在门口等。

   huì kāi wán le ma? wǒ zài ménkǒu děng

   Is the meeting over? I'll wait by the door.

4. 4

   until the pills run out

   药要吃完再去复诊。

   yào yào chī wán zài qù fùzhěn

   Finish the course, then come back for a check-up.

5. 5

   the bottom is out of reach

   这些活儿今天做不完。

   zhèxiē huór jīntiān zuò bu wán

   There's no finishing this lot today.

   完 is about the amount running out; 好 is about it turning out right and ready. 饭做完了 and 饭做好了 are not the same.