Explain this to me

This table contains stats for heroes' picks and bans.
Rank is used to sort heroes by winrate, taking number of their picks and bans into account. Higher rank means the hero is stronger. Rev-Rank (Reverse Rank) is used to show the least effective heroes with the most number of matches.
Balance metric estimates how balanced the meta is (0 to 100)

Median hero picks (mp): 4 - Median hero bans (mb): 4 - Matches: 21

Remove low picks (0.9mp) Remove low bans (0.9mb)

Balance rank	Winrate	Pickrate	Contest Rate
44.1	73.5	16.0	12.0

Hero	Matches	Contest Rate	Rank	Rev-Rank	Picked	Winrate	mp	Banned	Winrate	mb
Lifestealer	21	100.00%	100.00	43.75	4	100.00%	1.0	17	64.71%	4.3
Visage	15	71.43%	97.92	29.17	13	84.62%	3.3	2	50.00%	0.5
Dragon Knight	14	66.67%	95.83	35.42	8	75.00%	2.0	6	83.33%	1.5
Clockwerk	20	95.24%	93.75	72.92	7	71.43%	1.8	13	46.15%	3.3
Dark Seer	19	90.48%	91.67	70.83	13	61.54%	3.3	6	50.00%	1.5
Queen of Pain	13	61.90%	89.58	50.00	9	66.67%	2.3	4	50.00%	1.0
Batrider	21	100.00%	87.50	83.33	3	33.33%	0.8	18	55.56%	4.5
Io	17	80.95%	85.42	77.08	5	60.00%	1.3	12	50.00%	3.0
Juggernaut	14	66.67%	83.33	60.42	7	57.14%	1.8	7	57.14%	1.8
Nyx Assassin	21	100.00%	81.25	85.42	8	50.00%	2.0	13	46.15%	3.3
Sand King	9	42.86%	79.17	41.67	5	60.00%	1.3	4	75.00%	1.0
Bane	5	23.81%	77.08	18.75	1	100.00%	0.3	4	75.00%	1.0
Leshrac	15	71.43%	75.00	81.25	8	50.00%	2.0	7	42.86%	1.8
Shadow Demon	21	100.00%	72.92	91.67	12	33.33%	3.0	9	55.56%	2.3
Weaver	6	28.57%	70.83	31.25	3	66.67%	0.8	3	66.67%	0.8
Beastmaster	2	9.52%	68.75	8.33	2	100.00%	0.5	0	0.00%	0.0
Anti-Mage	12	57.14%	66.67	79.17	8	37.50%	2.0	4	75.00%	1.0
Magnus	19	90.48%	64.58	93.75	11	27.27%	2.8	8	62.50%	2.0
Luna	2	9.52%	62.50	10.42	1	100.00%	0.3	1	100.00%	0.3
Skywrath Mage	5	23.81%	60.42	33.33	3	66.67%	0.8	2	50.00%	0.5
Silencer	9	42.86%	58.33	62.50	4	50.00%	1.0	5	40.00%	1.3
Lone Druid	21	100.00%	56.25	97.92	8	50.00%	2.0	13	7.69%	3.3
Alchemist	9	42.86%	54.17	75.00	7	42.86%	1.8	2	50.00%	0.5
Rubick	17	80.95%	52.08	95.83	10	40.00%	2.5	7	14.29%	1.8
Keeper of the Light	14	66.67%	50.00	87.50	4	25.00%	1.0	10	40.00%	2.5
Lina	8	38.10%	47.92	68.75	4	25.00%	1.0	4	75.00%	1.0
Gyrocopter	19	90.48%	45.83	100.00	9	22.22%	2.3	10	30.00%	2.5
Chaos Knight	6	28.57%	43.75	58.33	4	50.00%	1.0	2	0.00%	0.5
Shadow Fiend	1	4.76%	41.67	6.25	1	100.00%	0.3	0	0.00%	0.0
Night Stalker	1	4.76%	41.67	12.50	1	100.00%	0.3	0	0.00%	0.0
Doom	1	4.76%	41.67	6.25	1	100.00%	0.3	0	0.00%	0.0
Clinkz	1	4.76%	41.67	6.25	1	100.00%	0.3	0	0.00%	0.0
Sven	2	9.52%	33.33	22.92	1	100.00%	0.3	1	0.00%	0.3
Morphling	2	9.52%	33.33	22.92	1	100.00%	0.3	1	0.00%	0.3
Drow Ranger	2	9.52%	29.17	27.08	2	50.00%	0.5	0	0.00%	0.0
Earthshaker	1	4.76%	27.08	16.67	0	0.00%	0.0	1	100.00%	0.3
Spectre	1	4.76%	27.08	16.67	0	0.00%	0.0	1	100.00%	0.3
Jakiro	4	19.05%	22.92	52.08	2	0.00%	0.5	2	100.00%	0.5
Mirana	4	19.05%	20.83	54.17	2	50.00%	0.5	2	0.00%	0.5
Puck	5	23.81%	18.75	64.58	2	0.00%	0.5	3	66.67%	0.8
Kunkka	3	14.29%	16.67	47.92	3	33.33%	0.8	0	0.00%	0.0
Templar Assassin	7	33.33%	14.58	89.58	5	0.00%	1.3	2	100.00%	0.5
Tinker	3	14.29%	12.50	45.83	1	0.00%	0.3	2	50.00%	0.5
Chen	3	14.29%	10.42	56.25	2	0.00%	0.5	1	100.00%	0.3
Nature's Prophet	2	9.52%	8.33	66.67	2	0.00%	0.5	0	0.00%	0.0
Storm Spirit	1	4.76%	6.25	25.00	0	0.00%	0.0	1	0.00%	0.3
Naga Siren	1	4.76%	4.17	37.50	1	0.00%	0.3	0	0.00%	0.0
Windranger	1	4.76%	4.17	41.67	1	0.00%	0.3	0	0.00%	0.0